Contents · Wall type 3: Masonry between independent panels 29 Junction requirements for wall type...

PAGE

Use of Guidance 3

The Requirements 5

Section 0: Performance 8

Performance standards 8

Section 1: Pre-completion testing 12

Introduction 12

Grouping 12

Sub grouping for new buildings 12

Sub grouping for material change of use 13

Sets of tests in dwelling-houses(including bungalows) 13

Sets of tests in flats with separating floorsbut without separating walls 13

Sets of tests in flats with a separating floorand a separating wall 13

Types of rooms for testing 13

Sets of tests in rooms for residentialpurposes 13

Properties sold before fitting-out 13

Normal programme of testing 14

Action following a failed set of tests 14

Remedial treatment 14

Material change of use 14

Approved manner of recordingpre-completion testing results 14

Section 2: Separating walls andassociated flanking constructionsfor new buildings 16

Introduction 16

Junctions between separating elementsand other building elements 16

Mass per unit area of walls 17

Plasterboard linings on separating andexternal masonry walls 17

Cavity widths in separating cavity masonrywalls 17

Wall ties in separating and external cavitymasonry walls 17

Corridor walls and doors 18

Refuse chutes 18

Wall type 1: Solid masonry 18

Junction requirements for wall type 1 20

Wall type 2: Cavity masonry 24


Wall type 3: Masonry between independentpanels 29


Wall type 4: Framed walls with absorbentmaterial 35


Section 3: Separating floors andassociated flanking constructionsfor new buildings 38

Introduction 38

Junctions between separating floors and other building elements 38

Beam and block floors 39

Mass per unit area of floors 39

Ceiling treatments 39

Floor type 1: Concrete base with ceilingand soft floor covering 40

Junction requirements for floor type 1 41

Floor type 2: Concrete base with ceiling andfloating floor 44

Floating floors (floating layers and resilientlayers) 45


Floor type 3: Timber frame base with ceilingand platform floor 49


Section 4: Dwelling-houses and flats formed by material change of use 53

Introduction 53

Work to existing construction 54


Wall treatment 1: Independent panel(s) withabsorbent material 55

Floor treatment 1: Independent ceiling withabsorbent material 56

Floor treatment 2: Platform floor withabsorbent material 57

Contents

Resistance to the passage of soundApproved Document E1

E

Stair treatment: Stair covering andindependent ceiling with absorbent material 58

Junction requirements for material changeof use 58

Section 5: Internal walls and floorsfor new buildings 60

Introduction 60

Doors 60

Layout 60

Junction requirements for internal walls 60

Junction requirements for internal floors 60

Internal wall type A: Timber or metalframes with plasterboard linings oneach side of frame 60

Internal wall type B: Timber or metalframes with plasterboard linings on eachside of frame and absorbent material 61

Internal wall type C: Concrete block wall,plaster or plasterboard finish on both sides 61

Internal wall type D: Aircrete block wallplaster or plasterboard finish on both sides 61

Internal floor type A: Concrete planks 62

Internal floor type B: Concrete beams withinfilling blocks, bonded screed and ceiling 62

Internal floor type C: Timber or metal joist,with wood based board and plasterboardceiling, and absorbent material 62

Section 6: Rooms for residential purposes 63

Introduction 63

Separating walls in new buildingscontaining rooms for residential purposes 63


Separating floors in new buildingscontaining rooms for residential purposes 63

Rooms for residential purposes resultingfrom a material change of use 63

Junction details 64

Room layout and building services designconsiderations 64

Section 7: Reverberation in the commoninternal parts of buildings containing flatsor rooms for residential purposes 65

Introduction 65

Method A 65

Method B 65

Report format 66

Worked example 66

Section 8: Acoustic conditions in schools 68

Annex A: Method for calculating massper unit area 69

A1 Wall mass 69

A2 Formula for calculation of wall leafmass per unit area 69

A3 Simplified equations 69

A4 Mass per unit area of surface finishes 70

A5 Mass per unit area of floors 70

Annex B: Procedures for soundinsulation testing 71

B1 Introduction 71

B2 Field measurement of sound insulationof separating walls and floors for thepurposes of Regulation 20A andRegulation 12A 71

B3 Laboratory measurements 72

B4 Information to be included in test reports 73

Annex C: Glossary 74

Annex D: References 76

D1 Standards 76

D2 Guidance 76

D3 Other legislation 76

Approved Document EResistance to the passage of sound2

E

THE APPROVED DOCUMENTSThis document is one of a series that has beenapproved and issued by the Secretary of Statefor the purpose of providing practical guidancewith respect to the requirements of Schedule 1to, and regulation 7 of, the Building Regulations2000 (SI 2000/2531) for England and Wales.SI 2000/2531 has been amended by the Building(Amendment) Regulations 2001 (SI 2001/3335),the Building (Amendment) Regulations 2002(SI 2002/440) and the Building (Amendment)(No. 2) Regulations 2002 (SI 2002/2871).

At the back of this document is a list of allthe documents that have been approvedand issued by the Secretary of State forthis purpose.

Approved Documents are intended to provideguidance for some of the more commonbuilding situations. However, there may well bealternative ways of achieving compliance withthe requirements. Thus there is no obligation toadopt any particular solution contained in anApproved Document if you prefer to meet therelevant requirement in some other way.

Other requirements

The guidance contained in an ApprovedDocument relates only to the particularrequirements of the Regulations which thedocument addresses. The building work willalso have to comply with the requirements ofany other relevant paragraphs in Schedule 1 tothe Regulations.

There are Approved Documents which giveguidance on each of the Parts of Schedule 1and on regulation 7.

LIMITATION ON REQUIREMENTSIn accordance with regulation 8, therequirements in Parts A to D, F to K and N(except for paragraphs H2 and J6) of Schedule1 to the Building Regulations do not requireanything to be done except for the purpose ofsecuring reasonable standards of health andsafety for persons in or about buildings (andany others who may be affected by buildings ormatters connected with buildings). This is oneof the categories of purpose for which buildingregulations may be made.

Paragraphs H2 and J6 are excluded fromregulation 8 because they deal directly withprevention of the contamination of water. PartsE and M (which deal, respectively, withresistance to the passage of sound, andaccess and facilities for disabled people) areexcluded from regulation 8 because theyaddress the welfare and convenience ofbuilding users. Part L is excluded fromregulation 8 because it addresses the

conservation of fuel and power. All thesematters are amongst the purposes, other thanhealth and safety, that may be addressed byBuilding Regulations.

MATERIALS AND WORKMANSHIPAny building work which is subject to therequirements imposed by Schedule 1 to theBuilding Regulations should, in accordancewith regulation 7, be carried out with propermaterials and in a workmanlike manner.

You may show that you have complied withregulation 7 in a number of ways. Theseinclude the appropriate use of a productbearing CE Marking in accordance with theConstruction Products Directive (89/106/EEC)1

as amended by the CE Marking Directive(93/68/EEC)2, or a product complying with anappropriate technical specification (as definedin those Directives), a British Standard, or analternative national technical specification ofany state which is a contracting party to theEuropean Economic Area which, in use, isequivalent, or a product covered by a nationalor European certificate issued by a EuropeanTechnical Approval issuing body, and theconditions of use are in accordance with theterms of the certificate. You will find furtherguidance in the Approved Documentsupporting regulation 7 on materials andworkmanship.

Independent certification schemesThere are many UK product certificationschemes. Such schemes certify compliancewith the requirements of a recogniseddocument which is appropriate to the purposefor which the material is to be used. Materialswhich are not so certified may still conform toa relevant standard.

Many certification bodies which approve suchschemes are accredited by UKAS.

Technical specificationsUnder section 1(a) of the Building Act, BuildingRegulations may be made for various purposesincluding health, safety, welfare, convenience,conservation of fuel and power and preventionof contamination of water. Standards andtechnical approvals are relevant guidance tothe extent that they relate to theseconsiderations. However, they may also

Use of guidance


ETHE BUILDING REGULATIONS 2000

1 As implemented by the Construction ProductsRegulations 1991 (S.I. 1991/1620).

2 As implemented by the Construction Products(Amendment) Regulations 1994 (S.I. 1994/3051).

address other aspects of performance such asserviceability, or aspects, which although theyrelate to the purposes listed above, are notcovered by the current Regulations.

When an Approved Document makes referenceto a named standard, the relevant version ofthe standard is the one listed at the end of thepublication. However, if this version has beenrevised or updated by the issuing standardsbody, the new version may be used as a sourceof guidance provided it continues to addressthe relevant requirements of the Regulations.

The appropriate use of a product whichcomplies with a European Technical Approvalas defined in the Construction ProductsDirective will meet the relevant requirements.

The Department intends to issue periodicamendments to its Approved Documents toreflect emerging harmonised EuropeanStandards. Where a national standard is to bereplaced by a European harmonised standard,there will be a co-existence period duringwhich either standard may be referred to. Atthe end of the co-existence period the nationalstandard will be withdrawn.

THE WORKPLACE (HEALTH,SAFETY AND WELFARE)REGULATIONS 1992The Workplace (Health, Safety and Welfare)Regulations 1992 contain some requirementswhich affect building design. The mainrequirements are now covered by the BuildingRegulations, but for further informationsee – Workplace health, safety and welfare.Workplace (Health, Safety and Welfare)Regulations 1992. Approved Code ofPractice L24. Published by HSE Books 1992(ISBN 0 7176 0413 6).

The Workplace (Health, Safety and Welfare)Regulations 1992 apply to the common parts offlats and similar buildings if people such ascleaners and caretakers are employed to workin these common parts. Where therequirements of the Building Regulations thatare covered by this Part do not apply todwellings, the provisions may still be requiredin the situations described above in order tosatisfy the Workplace Regulations.


E THE BUILDING REGULATIONS 2000

This Approved Document, which takes effecton 1 July 2003, deals with the Requirements ofPart E of Schedule 1 to the BuildingRegulations 2000 (as amended by SI 2002/2871).

[4] 1996 c.56. Section 4(1) was substituted by section 51 ofthe Education Act 1997 (c. 44).

The Requirements


ERESISTANCE TO THE PASSAGE OF SOUND

Protection against sound from other parts of thebuilding and adjoining buildings

E1. Dwelling-houses, flats and rooms for residentialpurposes shall be designed and constructed in sucha way that they provide reasonable resistance tosound from other parts of the same building andfrom adjoining buildings.

Protection against sound within a dwelling-house etc.

E2. Dwelling-houses, flats and rooms for residentialpurposes shall be designed and constructed in sucha way that –

(a) internal walls between a bedroom or a roomcontaining a water closet, and other rooms;and

(b) internal floors,

provide reasonable resistance to sound.

Reverberation in the common internal parts ofbuildings containing flats or rooms for residentialpurposes

E3. The common internal parts of buildings whichcontain flats or rooms for residential purposesshall be designed and constructed in such a way asto prevent more reverberation around the commonparts than is reasonable.

Acoustic conditions in schools

E4. (1) Each room or other space in a schoolbuilding shall be designed and constructedin such a way that it has the acousticconditions and the insulation againstdisturbance by noise appropriate to itsintended use.

(2) For the purposes of this Part - “school” hasthe same meaning as in section 4 of theEducation Act 1996[4]; and “schoolbuilding” means any building forming aschool or part of a school.

Requirement E2 does not apply to -

(a) an internal wall which contains a door;

(b) an internal wall which separates an en suitetoilet from the associated bedroom;

(c) existing walls and floors in a buildingwhich is subject to a material change of use.

Requirement E3 only applies to corridors, stairwells,hallways and entrance halls which give access to the flator room for residential purposes.

Requirement Limits on application


EAttention is drawn to the following extractsfrom The Building Regulations 2000 (asamended by SI 2002/2871).

Interpretation (Regulation 2) “room forresidential purposes” means a room, or suite ofrooms, which is not a dwelling-house or flatand which is used by one or more persons tolive and sleep in, including rooms in hotels,hostels, boarding houses, halls of residenceand residential homes but not including roomsin hospitals, or other similar establishments,used for patient accommodation.

Meaning of material change of use(Regulation 5)

For the purposes of paragraph 8 (1)(e) ofSchedule 1 to the Act and for the purposes ofthese Regulations, there is a material change ofuse where there is a change in the purposes forwhich or the circumstances in which a buildingis used, so that after the change-

(a) the building is used as a dwelling, wherepreviously it was not;

(b) the building contains a flat, wherepreviously it did not;

(c) the building is used as an hotel orboarding house, where previously it was not;

(d) the building is used as an institution,where previously it was not;

(e) the building is used as a public building,where previously it was not;

(f) the building is not a building described inClasses I to VI in Schedule 2, where previouslyit was;

(g) the building, which contains at least onedwelling, contains a greater or lesser number ofdwellings than it did previously;

(h) the building contains a room forresidential purposes, where previously it didnot; or

(i) the building, which contains at least oneroom for residential purposes, contains agreater or lesser number of such rooms than itdid previously.”

Requirements relating to material change ofuse (Regulation 6)

(1) Where there is a material change of useof the whole of a building, such work, if any,shall be carried out as is necessary to ensurethat the building complies with the applicablerequirements of the following paragraphs ofSchedule 1-

(a) in all cases,B1 (means of warning and escape)

B2 (internal fire spread - linings)

B3 (internal fire spread - structure)

B4(2) (external fire spread-roofs)

B5 (access and facilities for the fireservice)

F1 and F2 (ventilation)

G1 (sanitary conveniences and washingfacilities)

G2 (bathrooms)

H1 (foul water drainage)

H6 (solid waste storage)

J1 to J3 (combustion appliances)

L1 (conservation of fuel and power -dwellings);

L2 (conservation of fuel and power -buildings other than dwellings);

(b) in the case of a material change of usedescribed in regulations 5(c),(d), (e) or (f), A1 toA3 (structure);

(c) in the case of a building exceeding fifteenmetres in height, B4(1) (external fire spread -walls);

(d) in the case of material change of usedescribed in regulation 5(a), C4 (resistance toweather and ground moisture);

(e) in the case of a material change of usedescribed in regulation 5(a), (b), (c), (g), (h) or (i)E1 to E3.

(f) in the case of a material change of usedescribed in regulation 5(e), where the publicbuilding consists of or contains a school, E4(acoustic conditions in schools).

(2) Where there is a material change of use ofpart only of a building, such work, if any, shallbe carried out as is necessary to ensure that -

(a) that part complies in all cases with anyapplicable requirement referred to in paragraph(1)(a);

(b) in a case to which sub-paragraphs (b),(d), (e) or (f) of paragraph (1) apply, that partcomplies with the requirements referred to inthe relevant sub-paragraphs; and

(c) in the case to which sub-paragraph (c) ofparagraph (1) applies, the whole buildingcomplies with the requirement referred to inthat sub-paragraph.”

Sound insulation testing (Regulation 20A)

20A. (1) This regulation applies to –

(a) building work in relation towhich paragraph E1 of Schedule1 imposes a requirement; and

(b) work which is required to becarried out to a building toensure that it complies withparagraph E1 of Schedule 1 byvirtue of regulation 6(1)(e) or6(2)(b).

RESISTANCE TO THE PASSAGE OF SOUND

(2) Where this regulation applies, theperson carrying out the work shall,for the purpose of ensuringcompliance with paragraph E1 ofSchedule 1 –

(a) ensure that appropriate soundinsulation testing is carried outin accordance with a procedureapproved by the Secretary ofState; and

(b) give a copy of the results of thetesting referred to in sub-paragraph (a) to the localauthority.

(3) The results of the testing referred toin paragraph (2)(a) shall be –

(a) recorded in a manner approvedby the Secretary of State; and

(b) given to the local authority inaccordance with paragraph (2)(b)not later than the date on whichthe notice required by regulation15(4) is given.

Attention is drawn to the following extractfrom the Building (Approved Inspectors etc)Regulations 2000 (as amended by SI 2002 No 2872).

Sound insulation testing (Regulation 12A)

12A. (1) This regulation applies to –

(a) building work in relation towhich paragraph E1 of Schedule1 to the Principal Regulationsimposes a requirement; and

(b) work which is required to becarried out to a building to ensurethat it complies with paragraphE1 of Schedule 1 to the PrincipalRegulations by virtue ofregulation 6(1)(e) or 6(2)(b) ofthose Regulations,

which is the subject of an initial notice.

(2) Where this regulation applies, theperson carrying out the work shall,for the purpose of ensuringcompliance with paragraph E1 ofSchedule 1–

(a) ensure that appropriate soundinsulation testing is carried outin accordance with a procedureapproved by the Secretary ofState; and

(b) give a copy of the results of thetesting referred to in sub-paragraph (a) to the approvedinspector who gave the initialnotice.

(3) The results of the testing referred toin paragraph (2)(a) shall be –

(a) recorded in a manner approvedby the Secretary of State; and

(b) given to the approved inspectorin accordance with paragraph(2)(b) not later than 5 days aftercompletion of the work to whichthe initial notice relates.

For the purposes of Approved Document Ethe following definitions apply:

“Adjoining”: Adjoining dwelling-houses,adjoining flats, adjoining rooms for residentialpurposes and adjoining buildings are those indirect physical contact with another dwelling-house, flat, room for residential purpose orbuilding.

“Historic buildings”: Historic buildingsinclude:

(a) listed buildings

(b) buildings situated in conservation areas

(c) buildings which are of architectural andhistorical interest and which are referred to asa material consideration in a local authority’sdevelopment plan,

(d) buildings of architectural and historicalinterest within national parks, areas ofoutstanding natural beauty, and world heritagesites.


ERESISTANCE TO THE PASSAGE OF SOUND

Section 0: Performance


E

Performance standards0.1 In the Secretary of State’s view thenormal way of satisfying Requirement E1 willbe to build separating walls, separating floors,and stairs that have a separating function,together with the associated flankingconstruction, in such a way that they achievethe sound insulation values for dwelling-housesand flats set out in Table 1a, and the values forrooms for residential purposes (see definition inRegulation 2) set out in Table 1b. For walls thatseparate rooms for residential purposes fromadjoining dwelling-houses and flats, theperformance standards given in Table 1ashould be achieved

0.2 Regulation 20A of the Building Regulations2000 (as amended) and Regulation 12A of theBuilding (Approved Inspectors etc) Regulations2000 (as amended) apply to building work towhich Requirement E1 applies. Regulation 20Aapplies where building control is being carriedout by a local authority, and Regulation 12Aapplies where it is being carried out by anApproved Inspector. The normal way of satisfyingRegulation 20A or 12A will be to implement aprogramme of sound insulation testing accordingto the guidance set out in Section 1: Pre-completion testing of this Approved Document.

0.3 The sound insulation testing should becarried out in accordance with the proceduredescribed in Annex B of this Approved

Document, which is the procedure formallyapproved by the Secretary of State for thepurpose of paragraph (2)(a) of Regulation 20Aand paragraph (2)(a) of Regulation 12A. Theresults of the testing must be recorded in themanner described in paragraph 1.41 of Section1 of this Approved Document, which is themanner approved by the Secretary of State forthe purposes of paragraph (3)(a) of Regulation20A and paragraph (3)(a) of Regulation 12A.The test results must be given to the buildingcontrol body in accordance with the time limitsset down in Regulation 20A (for cases wherebuilding control is being done by the localauthority) or Regulation 12A (in cases where itis being done by an Approved Inspector).

0.4 The person carrying out the building workshould arrange for sound insulation testing to becarried out by a test body with appropriate thirdparty accreditation. Test bodies conductingtesting should preferably have UKAS accreditation(or a European equivalent) for field measurements.

0.5 Sections 2, 3, 4 and 6 of this ApprovedDocument give examples of constructions, which,if built correctly, should achieve the soundinsulation values for dwelling-houses and flats setout in Table 1a, and the values for rooms forresidential purposes set out in Table 1b. Theguidance in these sections is not exhaustive andother designs, materials or products may be usedto achieve the required performance.

PERFORMANCE

Table 1a: Dwelling-houses and flats - performance standards for separatingwalls, separating floors, and stairs that have a separating function.

Airborne sound insulation Impactsound insulation sound insulation

DnT,w + Ctr dB L’nT,w dB(Minimum values) (Maximum values)

Purpose built dwelling-houses and flats

Walls 45 -Floors and stairs 45 62

Dwelling-houses and flatsformed by material change of use


Table 1b: Rooms for residential purposes - performance standards for separatingwalls, separating floors, and stairs that have a separating function.

Airborne sound insulation Impactsound insulation sound insulation

DnT,w + Ctr dB L’nT,w dB(Minimum values) (Maximum values)

Purpose built rooms for residential purposes


Rooms for residential purposesformed by material change of use



E

0.6 Buildings constructed from sub-assembliesthat are delivered newly made or selected fromstock are no different from any other new buildingand must comply with all requirements inSchedule 1 of the Building Regulations 2000(asamended). In some applications, such asbuildings that are constructed to be temporarydwelling-houses, flats, rooms for residentialpurposes, or school buildings, the provision ofreasonable resistance to the passage of soundmay vary depending upon the circumstances inthe particular case. For example, (a) a buildingcreated by dismantling, transporting and re-erecting the sub-assemblies on the samepremises would normally be considered to meetthe requirements, (b) a building constructed fromsub-assemblies obtained from other premises orfrom stock manufactured before 1st July 2003,would normally be considered to meet therequirements if it satisfies the relevantrequirements of Part E that were applicable in1992, or for school buildings, the relevantprovisions relating to acoustics set out in the1997 edition of Building Bulletin 87 (ISBN 011271013 1).

0.7 In the case of some historic buildingsundergoing a material change of use, it may notbe practical to improve the sound insulation tothe standards set out in Tables 1a and 1b. Theneed to conserve the special characteristics ofsuch historic buildings needs to be recognised1,and in such work, the aim should be to improvesound insulation to the extent that it ispractically possible, always provided that thework does not prejudice the character of thehistoric building, or increase the risk of long-term deterioration to the building fabric orfittings. In arriving at an appropriate balancebetween historic building conservation andimproving sound insulation it would beappropriate to take into account the advice ofthe local planning authority’s conservationofficer. In such cases it will be reasonable toimprove the sound insulation as much as ispractical, and to affix a notice showing thesound insulation value(s) obtained by testing inaccordance with Regulation 20A or 12A, in aconspicuous place inside the building.

0.8 The performance standards set out inTables 1a and 1b are appropriate for walls,floors and stairs that separate spaces used fornormal domestic purposes. A higher standardof sound insulation may be required betweenspaces used for normal domestic purposes and

communal or non-domestic purposes. In thesesituations the appropriate level of soundinsulation will depend on the noise generatedin the communal or non-domestic space.Specialist advice may be needed to establish ifa higher standard of sound insulation isrequired, and if so, to determine theappropriate level.

0.9 In the Secretary of State’s view thenormal way of satisfying Requirement E2 willbe to use constructions for new walls andfloors within a dwelling-house, flat or room forresidential purposes, that provide thelaboratory sound insulation values set out inTable 2. Test bodies conducting testing shouldpreferably have UKAS accreditation (or aEuropean equivalent) for laboratorymeasurements. It is not intended thatperformance should be verified by testing onsite.

0.10 Section 5 gives examples ofconstructions that should achieve thelaboratory values set out in Table 2. Theguidance in these sections is not exhaustiveand other designs, materials or products maybe used to achieve the required performance.

0.11 In the Secretary of State’s view thenormal way of satisfying Requirement E3 willbe to apply the sound absorption measuresdescribed in Section 7 of this ApprovedDocument, or other measures of similareffectiveness.

0.12 In the Secretary of State’s view the normalway of satisfying Requirement E4 will be tomeet the values for sound insulation,reverberation time and indoor ambient noisewhich are given in Section 1 of BuildingBulletin 93 ‘The Acoustic Design of Schools’,produced by DfES and published by theStationery Office (ISBN 0 11 271105 7) (to bepublished during 2003).

0.13 Diagrams 0.1 to 0.3 illustrate the relevantparts of the building that should be protectedfrom airborne and impact sound in order tosatisfy Requirements E1 and E2.

PERFORMANCE

Table 2: Laboratory values for new internal walls and floors within:dwelling-houses, flats and rooms for residential purposes, whetherpurpose built or formed by material change of use.

Airborne sound insulationRw dB

(Minimum values)

Walls 40Floors 40

1 BS 7913 The principles of the conservation of historicbuildings, 1998 provides guidance on the principlesthat should be applied when proposing work onhistoric buildings


E PERFORMANCE

Flat or room for residential purposes;Other parts of the same building;

Separating floor

Separating floor

Sep

arat

ing

wal

l

Flat or roomfor residential

purposes

Other partsof the same

building

Any dwelling-house, flat orroom for residential purposes

to which Requirement E1 applies

Adjoining dwelling-house, flat orroom for residential purposes;

Other parts of the same building;Adjoining building;

Refuse chutes

KEY:

Impact sound insulation

Airborne sound insulation

Diagram 0-1: Requirement E1

Inte

rnal

wal

l

Any roomto which requirement E2(a) applies

Dwelling-house, flat or room for residential purposes

Bedroom or a roomcontaining a water closet

KEY: Airborne sound insulation

Diagram 0-2: Requirement E2(a)


EPERFORMANCE

Any roomto which requirement E2(b) applies

Internal floor

Dwelling-house, flat or room for residential purposes

Any roomto which requirement E2(b) applies

KEY: Airborne sound insulation

Diagram 0-3: Requirement E2(b)


E

Introduction1.1 This section provides guidance on anappropriate programme of sound insulationtesting for a sample of properties, underRegulation 20A of the Building Regulations andRegulation 12A of the Approved InspectorsRegulations.

1.2 Sound insulation testing to demonstratecompliance with Requirement E1 should becarried out on site as part of the constructionprocess, and in this Approved Document it isreferred to as pre-completion testing. UnderRegulation 20A and Regulation 12A, the duty ofensuring that appropriate sound insulationtesting is carried out falls on the person carryingout the building work, who is also responsiblefor the cost of the testing. Therefore, theguidance in this section is addressed in the firstplace to persons carrying out the work (and totesting bodies employed by them). However, it isalso addressed to building control bodies, asthe Secretary of State expects building controlbodies to determine, for each relevantdevelopment, the properties selected for testing.

1.3 Testing should be carried out for:

(a) purpose built dwelling-houses and flats;

(b) dwelling-houses and flats formed bymaterial change of use;

(c) purpose built rooms for residentialpurposes;

(d) rooms for residential purposes formedby material change of use.

1.4 The normal programme of testing isdescribed in paragraphs 1.29 to 1.31.

1.5 The testing procedure formally approvedby the Secretary of State is described in AnnexB: Procedures for sound insulation testing.

1.6 The performance standards that shouldbe demonstrated by pre-completion testing areset out in Section 0: Performance - Tables 1aand 1b. The sound insulation values in thesetables have a built-in allowance formeasurement uncertainty, so if any test showsone of these values not to have been achievedby any margin, the test has been failed.

1.7 The person carrying out the building workshould ensure that the guidance onconstruction given in this Approved Document,or in another suitable source, is followedproperly to minimize the chances of a failedtest. Where additional guidance is required,specialist advice on the building design shouldbe sought at an early stage.

1.8 Testing should not be carried outbetween living spaces, corridors, stairwellsor hallways.

1.9 Tests should be carried out betweenrooms or spaces that share a common area ofseparating wall or separating floor.

1.10 Tests should be carried out once thedwelling-houses, flats or rooms for residentialpurposes either side of a separating element areessentially complete, except for decoration.Impact sound insulation tests should be carriedout without a soft covering (e.g. carpet, foambacked vinyl etc) on the floor. For exceptions andfurther information on floor coverings and testingsee Annex B: paragraphs B2.13 and B2.14.

Grouping1.11 The results of tests only apply to theparticular constructions tested but are indicativeof the performance of others of the same type inthe same development. Therefore, in order formeaningful inferences to be made from tests, itis essential that developments are considered asa number of notional groups, with the sameconstruction type within each group.

1.12 Grouping should be carried out accordingto the following criteria. Dwelling-houses(including bungalows), flats and rooms forresidential purposes should be considered asthree separate groups. In addition, if significantdifferences in construction type occur withinany of these groups, sub-groups should beestablished accordingly.

1.13 The following guidance should allowsuitable sub-grouping in most circumstances.

Sub-grouping for new buildings1.14 For dwelling-houses (includingbungalows), sub-grouping should be by type ofseparating wall. For flats, sub-grouping shouldbe by type of separating floor and type ofseparating wall. Rooms for residential purposesshould be grouped using similar principles.

1.15 The construction of flanking elements(e.g. walls, floors, cavities) and their junctionsare also important. Where there are significantdifferences between flanking details, furthersub-grouping will be necessary.

1.16 Sub-grouping may not be necessary fordwelling-houses, flats and rooms for residentialpurposes that have the same separating walland/or separating floor construction, with thesame associated flanking construction(s), andwhere the room dimensions and layouts arebroadly similar.

1.17 Some dwelling-houses, flats or rooms forresidential purposes may be considered to haveunfavourable features: an example could be flatswith large areas of flanking wall without a windowat the gable end. It would be inappropriate forthese to be included as part of a group and theseshould form their own sub-group(s).

Section 1: Pre-completion testingPRE-COMPLETION TESTING


E

Sub-grouping for material changeof use1.18 The same principles as for new buildingsapply, but in practice significant differences aremore likely to occur between separating walland/or separating floor constructions as well asthe associated flanking construction(s) in adevelopment. More sub-groups may thereforebe required, and group sizes may be smaller.Building control bodies should exercisejudgement when setting up sub-groups.

Sets of tests in dwelling-houses(including bungalows)1.19 Normally, one set of tests shouldcomprise two individual sound insulation tests(two airborne tests):

• A test of insulation against airbornesound between one pair of rooms(where possible suitable for use asliving rooms) on opposite sides of theseparating wall.

• A test of insulation against airbornesound between another pair of rooms(where possible suitable for use asbedrooms) on opposite sides of theseparating wall.

Sets of tests in flats withseparating floors but withoutseparating walls1.20 Normally, one set of tests shouldcomprise four individual sound insulation tests(two airborne tests, two impact tests):

• Tests of insulation against bothairborne and impact sound betweenone pair of rooms (where possiblesuitable for use as living rooms) onopposite sides of the separating floor.

• Tests of insulation against bothairborne and impact sound betweenanother pair of rooms (where possiblesuitable for use as bedrooms) onopposite sides of the separating floor.

Sets of tests in flats with aseparating floor and a separatingwall1.21 Normally, one set of tests shouldcomprise six individual sound insulation tests(four airborne tests, two impact tests):

• A test of insulation against airbornesound between one pair of rooms(where possible suitable for use asliving rooms) on opposite sides of theseparating wall.

• A test of insulation against airbornesound between another pair of rooms(where possible suitable for use asbedrooms) on opposite sides of theseparating wall.

• Tests of insulation against bothairborne and impact sound betweenone pair of rooms (where possiblesuitable for use as living rooms) onopposite sides of the separating floor.

• Tests of insulation against bothairborne and impact sound betweenanother pair of rooms (where possiblesuitable for use as bedrooms) onopposite sides of the separating floor.

1.22 To conduct a full set of tests, access toat least three flats will be required.

Types of rooms for testing1.23 It is preferable that each set of testscontains individual tests in bedrooms and livingrooms.

1.24 Where pairs of rooms on either side ofthe separating element are different (e.g. abedroom and a study, a living room and abedroom), at least one of the rooms in one ofthe pairs should be a bedroom and at least oneof the rooms in the other pair should be a livingroom.

1.25 Where the layout has only one pair ofrooms on opposite sides of the entire area ofseparating wall or floor between two dwelling-houses, flats or rooms for residential purposesthen the number of airborne and impact soundinsulation tests set out in paragraphs 1.19 to1.21 may be reduced accordingly.

1.26 The approved procedure described inAnnex B includes requirements relating torooms.

Sets of tests in rooms forresidential purposes1.27 To conduct a set of tests, the soundinsulation between the main rooms should bemeasured according to the principles set out inthis Section for new buildings and materialchange of use, but adapting them to suit thecircumstances.

Properties sold before fitting-out1.28 Some properties, for example loftapartments, may be sold before being fittedout with internal walls and other fixtures andfittings. Measurements of sound insulationshould be made between the available spaces,according to the principles set out in thisSection. Steps should be taken to ensure thatfitting out will not adversely affect the soundinsulation. Some guidance on internal wall andfloor constructions is given in Section 5.Junction details between these internal walls

PRE-COMPLETION TESTING


Eand floors and separating walls and floors aredescribed in Sections 2 and 3.

Normal programme of testing1.29 Building control bodies should consultwith developers on likely completion times onsite, and ask for one set of tests to be carriedout between the first dwelling-houses, flats orrooms for residential purposes scheduled forcompletion and/or sale in each group or sub-group. This applies regardless of the intendedsize of the group or sub-group. Therefore if asite comprises only one pair of dwelling-houses, flats or rooms for residential purposes,they should be tested.

1.30 As further properties on a developmentbecome ready for testing, building controlbodies should indicate at what point(s) theywish any further set(s) of tests to beconducted. Assuming no tests are failed,building control bodies should stipulate at leastone set of tests for every ten dwelling-houses,flats or rooms for residential purposes in agroup or sub-group.

1.31 Testing should be conducted morefrequently at the beginning of a series ofcompletions than towards the end, to allow anypotential problems to be addressed at an earlystage. However, on large developments testingshould be carried out over a substantial part ofthe construction period.

Action following a failed set oftests1.32 A set of tests is failed if any of itsindividual tests of airborne or impact soundinsulation do not show sound insulation valuesequal to or better than those set out in Section0: Performance - Tables 1a and 1b.

1.33 In the event of a failed set of tests,appropriate remedial treatment should beapplied to the rooms that failed the test.

1.34 A failed set of tests raises questions overthe sound insulation between other roomssharing the same separating element in thedwelling-houses, flats or rooms for residentialpurposes in which the tests were conducted.The developer should demonstrate to thebuilding control body’s satisfaction that theserooms meet the performance standards.Normally this would be done by (a) additionaltesting, and/or (b) applying the appropriateremedial treatment to the other rooms and/or(c) demonstrating that the cause of failure doesnot occur in other rooms.

1.35 A failed set of tests raises questionsover properties between which tests have notbeen carried out. The developer shoulddemonstrate to the building control body’ssatisfaction that such properties meet theperformance standards. Once a dwelling-house, flat or room for residential purposes is

occupied, any action affecting it should be amatter for local negotiation.

1.36 After a failed set of tests, the rate oftesting should be increased until the buildingcontrol body is satisfied that the problem hasbeen solved.

Remedial treatment1.37 Appropriate remedial treatment should beapplied following a failed set of tests. It isessential that remedial work is appropriate tothe cause of failure. Guidance is available inBRE information paper IP 14/02.

1.38 Where the cause of failure is attributed tothe construction of the separating and/orassociated flanking elements, other rooms thathave not been tested may also fail to meet theperformance standards. Therefore, remedialtreatment may be needed in rooms other thanthose in which the tests were conducted.

1.39 Where remedial treatment has beenapplied, the building control body should besatisfied with its efficacy. Normally this willbe assessed through additional soundinsulation testing.

Material change of use1.40 As stated in Section 0, in the case of somehistoric buildings undergoing a material changeof use, it may not always be practical to achievethe sound insulation values set out in Section 0:Performance - Tables 1a and 1b. However, insuch cases building control bodies should besatisfied that everything reasonable has beendone to improve the sound insulation. Testsshould be carried out, and the results displayedas indicated in Section 0: paragraph 0.7.

Approved manner of recordingpre-completion testing results1.41 In order to satisfy the requirements ofparagraph (3)(a) of Regulation 20A orRegulation 12A, the test report of a set oftests (where set of tests has the meaning givenin paragraphs 1.19 - 1.21 and 1.27) mustcontain at least the following information, in theorder below:

1. Address of building.

2. Type(s) of property. Use the definitions inRegulation 2: dwelling-house, flat, roomfor residential purposes. State if thebuilding is a historic building (seedefinition in the section on Requirementsof this Approved Document).

3. Date(s) of testing.

4. Organisation carrying out testing,including:

(a) name and address;

PRE-COMPLETION TESTING


EPRE-COMPLETION TESTING

(b) third party accreditation number (e.g.UKAS or European equivalent);

(c) name(s) of person(s) in charge of test;

(d) name(s) of client(s).

5. A statement (preferably in a table) givingthe following information:

(a) the rooms used for each test withinthe set of tests;

(b) the measured single-number quantity(DnT,w + Ctr for airborne soundinsulation and L’nT,w for impact soundinsulation) for each test within the setof tests;

(c) the sound insulation values thatshould be achieved according to thevalues set out in Section 0:Performance - Table 1a or 1b, and

(d) an entry stating “Pass” or “Fail” foreach test within the set of testsaccording to the sound insulationvalues set out in Section 0:Performance - Table 1a or 1b.

6. Brief details of test, including:

(a) equipment;

(b) a statement that the test proceduresin Annex B have been followed. If theprocedure could not be followedexactly then the exceptions shouldbe described and reasons given;

(c) source and receiver room volumes(including a statement on whichrooms were used as source rooms);

(d) results of tests shown in tabular andgraphical form for third octave bandsaccording to the relevant part of theBS EN ISO 140 series and BS EN ISO717 series, including:

(i) single-number quantities and thespectrum adaptation terms;

(ii) DnT and L’nT data from which thesingle-number quantities arecalculated.


E

Introduction 2.1 This Section gives examples of wall typeswhich, if built correctly, should achieve theperformance standards set out in Section 0:Performance - Table 1a.

2.2 The guidance in this section is notexhaustive and other designs, materials orproducts may be used to achieve theperformance standards set out in Section 0:Performance - Table 1a. Advice should besought from the manufacturer or otherappropriate source.

2.3 The walls are grouped into four maintypes. See Diagram 2-1.

2.4 Wall type 1: Solid masonryThe resistance to airborne sounddepends mainly on the mass per unit areaof the wall.

2.5 Wall type 2: Cavity masonryThe resistance to airborne sounddepends on the mass per unit area of theleaves and on the degree of isolationachieved. The isolation is affected byconnections (such as wall ties andfoundations) between the wall leaves andby the cavity width.

2.6 Wall type 3: Masonry betweenindependent panelsThe resistance to airborne sounddepends partly on the type and mass perunit area of the core, and partly on theisolation and mass per unit area of theindependent panels.

2.7 Wall type 4: Framed walls with absorbentmaterial The resistance to airborne sound dependson the mass per unit area of the leaves, theisolation of the frames, and the absorptionin the cavity between the frames.

2.8 Within each wall type the constructions areranked, as far as possible, with constructionsproviding higher sound insulation given first.

Junctions between separatingwalls and other building elements2.9 In order for the construction to be fullyeffective, care should be taken to correctlydetail the junctions between the separating walland other elements, such as floors, roofs,external walls and internal walls.Recommendations are also given for theconstruction of these elements, where it isnecessary to control flanking transmission.Notes and diagrams explain the junction detailsfor each of the separating wall types.

SEPARATING WALLS (NEW BUILDINGS)

Section 2: Separating walls and associatedflanking constructions for new buildings

plaster

masonry

independentpanels

independentframes

masonry core

mineral wool

(a) Wall type 1

(b) Wall type 2

(c) Wall type 3

(d) Wall type 4

cavity

plaster

masonry

cavity

Diagram 2-1: Types of separating wall


E

2.10 Table 2.1 indicates the inclusion ofguidance in this document on the junctionsthat may occur between each of the fourseparating wall types and various attachedbuilding elements.

Mass per unit area of walls2.11 The mass per unit area of a wall isexpressed in kilograms per square metre(kg/m2). The method for calculating mass perunit area is shown in Annex A.

2.12 The density of the materials used (and onwhich the mass per unit area of the walldepends) is expressed in kilograms per cubicmetre (kg/m3). When calculating the mass perunit area for bricks and blocks use the densityat the appropriate moisture content from Table3.2, CIBSE Guide A (1999).

2.13 The guidance describes constructions thatuse blocks without voids. For blocks withvoids, seek advice from the manufacturer.

Plasterboard linings on separatingand external masonry walls2.14 The guidance describes someconstructions with only wet finishes. For dryfinishes, seek advice from the manufacturer.

2.15 Wherever plasterboard is recommended,or the finish is not specified, a drylininglaminate of plasterboard with mineral wool maybe used. For other drylining laminates, seekadvice from the manufacturer.

2.16 Plasterboard linings should be fixedaccording to manufacturer’s instructions.

Cavity widths in separating cavitymasonry walls2.17 Recommended cavity widths areminimum values.

Wall ties in separating andexternal cavity masonry walls2.18 Suitable wall ties for use in masonrycavity walls are indicated in the guidance byreference to either tie type A or B.

2.19 Tie type A Connect the leaves of a cavity masonry wallonly where necessary by butterfly ties asdescribed in BS 1243:1978 Metal ties for cavitywall construction, and spaced as required forstructural purposes (BS 5628-3:2001 Code ofpractice for use of masonry. Materials andcomponents, design and workmanship, whichlimits this tie type and spacing to cavity widthsof 50 mm to 75 mm with a minimum masonryleaf thickness of 90 mm). Alternatively, use wallties with an appropriate measured dynamicstiffness for the cavity width. The specificationfor wall ties of dynamic stiffness, kXmm in MN/mwith a cavity width of X mm and n ties/m2 isn.kXmm<4.8 MN/m3.

2.20 Tie type B (for use only in externalmasonry cavity walls where tie type A does notsatisfy the requirements of Building RegulationPart A - Structure)


Separating wall type

Building element attached to separating wall Type 1 Type 2 Type 3 Type 4

External cavity wall with masonry inner leaf G G G N

External cavity wall with timber frame inner leaf G G G G

External solid masonry wall N N N N

Internal wall - framed G G G G

Internal wall - masonry G G X G

Internal floor - timber G G G G

Internal floor - concrete G G G N

Ground floor - timber G G G G

Ground floor - concrete G G G G

Ceiling and roof space G G G G

For flats the following may also apply:

Separating floor type 1 – concrete base with ceiling and soft floor covering See Guidance in Section 3, Separating

Separating floor type 2 – concrete base with ceiling and floating floor floors and associated flanking

Separating floor type 3 – timber frame base with ceiling and platform floor constructions for new buildings

Key: G = guidance available; N = no guidance available (seek specialist advice); X = do not build

Note: Where any building element functions as a separating element (e.g. a ground floor that is also a separating floor for a basement flat)then the separating element requirements should take precedence.

Table 2.1 Separating wall junctions reference table.


EConnect the leaves of a cavity masonry wallonly where necessary by double-triangle ties asdescribed in BS 1243:1978 Metal ties for cavitywall construction, and spaced as required forstructural purposes (BS 5628-3: 2001 Code ofpractice for use of masonry. Materials andcomponents, design and workmanship, whichlimits this tie type and spacing to cavity widthsof 50 mm to 75 mm with a minimum masonryleaf thickness of 90 mm). Alternatively, use wallties with an appropriate measured dynamicstiffness for the cavity width. The specificationfor wall ties of dynamic stiffness, kXmm in MN/mwith a cavity width of X mm and n ties/m2 isn.kXmm<113 MN/m3.

Note: In external cavity masonry walls, tie typeB may decrease the airborne sound insulationdue to flanking transmission via the externalwall leaf compared to tie type A.

2.21 Measurements of the wall tie dynamicstiffness, kXmm should be carried out accordingto BRE Information Paper, IP 3/01.

2.22 The number of ties per square metre, n,is calculated from the horizontal and vertical tiespacing distances, Sx and Sy in metres using n = 1 / (Sx.Sy). Example: For horizontal andvertical tie spacing distances of 0.9 m and 0.45 m, n is 2.5 ties/m2.

2.23 If kXmm is not available for the requiredcavity width, it is acceptable to use availablekXmm data for X mm values less than therequired cavity width to calculate n.kXmm.

2.24 All wall ties and spacings specified usingthe dynamic stiffness parameter should alsosatisfy the Requirements of Building RegulationPart A - Structure.

Corridor walls and doors2.25 The separating walls described in thissection should be used between corridors androoms in flats, in order to control flankingtransmission and to provide the requiredsound insulation. However, it is likely that thesound insulation will be reduced by thepresence of a door.

2.26 Ensure that any door has good perimetersealing (including the threshold where practical)and a minimum mass per unit area of 25 kg/m2

or a minimum sound reduction index of 29 dB Rw

(measured according to BS EN ISO 140-3:1995and rated according to BS EN ISO 717-1:1997).The door should also satisfy the Requirements ofBuilding Regulation Part B - Fire safety.

2.27 Noisy parts of the building shouldpreferably have a lobby, double door or highperformance doorset to contain the noise. Wherethis is not possible, nearby flats should havesimilar protection. However, there should be asufficient number of flats that are suitable fordisabled access, see Building Regulation Part M- Access and facilities for disabled people.

Refuse chutes2.28 A wall separating a habitable room orkitchen and a refuse chute should have a massper unit area (including any finishes) of at least1320 kg/m2. A wall separating a non-habitableroom from a refuse chute should have a massper unit area (including any finishes) of at least220 kg/m2.

Wall type 1: Solid masonry2.29 The resistance to airborne sound dependsmainly on the mass per unit area of the wall.

Constructions

2.30 Three wall type 1 constructions (types 1.1,1.2, and 1.3) are described in this guidance.

2.31 Details of how junctions should be madeto limit flanking transmission are also describedin this guidance.

2.32 Points to watch


Do

a. Do fill and seal all masonry joints withmortar.

b. Do lay bricks frog up to achieve therequired mass per unit area and avoidair paths.

c. Do use bricks/blocks that extend tothe full thickness of the wall.

d. Do ensure that an external cavity wallis stopped with a flexible closer at thejunction with a separating wall, unlessthe cavity is fully filled with mineralwool or expanded polystyrene beads(seek manufacturer’s advice for othersuitable materials).

e. Do control flanking transmission fromwalls and floors connected to theseparating wall as described in theguidance on junctions.

f. Do stagger the position of sockets onopposite sides of the separating wall.

g. Do ensure that flue blocks will notadversely affect the sound insulationand that a suitable finish is used overthe flue blocks (see BS 1289-1:1986and seek manufacturer’s advice).


E

2.33 Wall type 1.1 Dense aggregate concreteblock, plaster on both room faces (see Diagram 2-2)

• minimum mass per unit areaincluding plaster 415 kg/m2

• 13 mm plaster on both room faces

• use blocks that are laid flat to the fullthickness of the wall

2.34 Wall type 1.2 Dense aggregate concretecast in-situ, plaster on both room faces (seeDiagram 2-3)


• plaster on both room faces


Example of wall type 1.1

The required mass per unit area would beachieved by using

• 215 mm block laid flat

• block density 1840 kg/m3

• 110 mm coursing

• 13 mm lightweight plaster (minimummass per unit area 10 kg/m2) on bothroom faces

This is an example only. See Annex A for asimplified method of calculating mass perunit area. Alternatively use manufacturer’sactual figures where these are available.



• 190 mm concrete

• concrete density 2200 kg/m3



Do not

a. Do not try and convert a cavity separatingwall to a type 1 (solid masonry) separatingwall by inserting mortar or concrete intothe cavity between the two leaves.

b. Do not use deep sockets and chases inthe separating wall, and do not placesockets back to back.

c. Do not create a junction between a solidwall type 1 and a cavity wall type 2 inwhich the cavity wall is bridged by thesolid wall.

Diagram 2-2: Wall type 1.1

SECTION


SECTION


E2.35 Wall type 1.3 Brick, plaster on both roomfaces (see Diagram 2-4)



• bricks to be laid frog up, coursedwith headers

Junction requirements for walltype 1 Junctions with an external cavity wall withmasonry inner leaf

2.36 Where the external wall is a cavity wall:

(a) the outer leaf of the wall may be of anyconstruction, and

(b) the cavity should be stopped with aflexible closer (see Diagram 2-5) unless thecavity is fully filled with mineral wool orexpanded polystyrene beads (seekmanufacturer’s advice for other suitablematerials).

2.37 The separating wall should be joined tothe inner leaf of the external cavity wall by oneof the following methods:

(a) Bonded. The separating wall should bebonded to the external wall in such a way thatthe separating wall contributes at least 50% ofthe bond at the junction. See Diagram 2-6.

(b) Tied. The external wall should abut theseparating wall and be tied to it. See Diagram2-7. Also, see Building Regulation Part A -Structure.

2.38 The masonry inner leaf should have amass per unit area of at least 120 kg/m2

excluding finish. However, there is no minimummass requirement where there are openings inthe external wall (see Diagram 2-8) that are:

(a) not less than 1 metre high, and

(b) on both sides of the separating wall atevery storey, and

(c) not more than 700 mm from the face ofthe separating wall on both sides.

2.39 Where there is also a separating floorthen the requirement for a minimum mass perunit area of 120 kg/m2 excluding finish shouldalways apply, irrespective of the presence orabsence of openings.




• 215 mm brick

• brick density 1610 kg/m3

• 75 mm coursing




SECTION


E

Junctions with an external cavity wall withtimber frame inner leaf



(b) the cavity should be stopped with aflexible closer. See Diagram 2-9.

2.41 Where the inner leaf of an external cavitywall is of framed construction, the framed innerleaf should:

(a) abut the separating wall, and

(b) be tied to it with ties at no more than 300 mm centres vertically.


cavity stop

Diagram 2-5: Wall type 1 – external cavitywall with masonry inner leaf

Diagram 2-6: Wall type 1 – bondedjunction – masonry innerleaf of external cavity wallwith solid separating wall

PLAN

cavity stop

tied junction

internalmasonry wall

separating wall type 1

Diagram 2-7: Wall type 1 – tied junction– external cavity wall withinternal masonry wall

separating wall

x not more than 700 mmandy not less than 1 m

masonry inner leaf ofexternal cavity wall

xy

Diagram 2-8: Wall type 1 – position ofopenings in masonry innerleaf of external cavity wall


EThe wall finish of the framed inner leaf of theexternal wall should be:

(a) one layer of plasterboard, or

(b) two layers of plasterboard where there isa separating floor

(c) each sheet of plasterboard to be ofminimum mass per unit area 10 kg/m2, and

(d) all joints should be sealed with tape orcaulked with sealant.

Junctions with an external solid masonry wall

2.42 No guidance available (seek specialistadvice).

Junctions with internal framed walls

2.43 There are no restrictions on internalframed walls meeting a type 1 separating wall.

Junctions with internal masonry walls

2.44 Internal masonry walls that abut a type 1separating wall should have a mass per unitarea of at least 120 kg/m2 excluding finish.

Junctions with internal timber floors

2.45 If the floor joists are to be supported on atype 1 separating wall then they should besupported on hangers and should not be builtin. See Diagram 2-10.

Junctions with internal concrete floors

2.46 An internal concrete floor slab may onlybe carried through a type 1 separating wall ifthe floor base has a mass per unit area of atleast 365 kg/m2. See Diagram 2-11.

2.47 Internal hollow-core concrete plank floorsand concrete beams with infilling block floorsshould not be continuous through a type 1separating wall.

2.48 For internal floors of concrete beams withinfilling blocks, avoid beams built in to theseparating wall unless the blocks in the floor fillthe space between the beams where theypenetrate the wall.

Junctions with timber ground floors

2.49 If the floor joists are to be supported on atype 1 separating wall then they should besupported on hangers and should not be built in.

2.50 See Building Regulation Part C - Sitepreparation and resistance to moisture, andBuilding Regulation Part L - Conservation offuel and power.


cavity stop

Diagram 2-9: Wall type 1 – externalcavity wall with timberframe inner leaf

PLAN

hanger

Diagram 2-10: Wall type 1 – internaltimber floor

SECTION

concrete slab may be carriedthrough if mass per unit areais at least 365 kg/m2

Diagram 2-11: Wall type 1 – internalconcrete floor

SECTION


EJunctions with concrete ground floors

2.51 The ground floor may be a solid slab, laidon the ground, or a suspended concrete floor.A concrete slab floor on the ground may becontinuous under a type 1 separating wall. SeeDiagram 2-12.

2.52 A suspended concrete floor may onlypass under a type 1 separating wall if the floorhas a mass of at least 365 kg/m2.

2.53 Hollow core concrete plank and concretebeams with infilling block floors should not becontinuous under a type 1 separating wall.


Junctions with ceiling and roof

2.55 Where a type 1 separating wall is used itshould be continuous to the underside of the roof.

2.56 The junction between the separating walland the roof should be filled with a flexiblecloser which is also suitable as a fire stop. SeeDiagram 2-13.

2.57 Where the roof or loft space is not ahabitable room and there is a ceiling with aminimum mass per unit area of 10 kg/m2 withsealed joints, then the mass per unit area ofthe separating wall above the ceiling may bereduced to 150 kg/m2. See Diagram 2-13.

2.58 If lightweight aggregate blocks of densityless than 1200 kg/m3 are used above ceilinglevel, then one side should be sealed withcement paint or plaster skim.

2.59 Where there is an external cavity wall, thecavity should be closed at eaves level with asuitable flexible material (e.g. mineral wool).See Diagram 2-14.

Note: A rigid connection between the inner andexternal wall leaves should be avoided. If arigid material is used, then it should only berigidly bonded to one leaf. See BRE BR 262,Thermal Insulation: avoiding risks, section 2.3.

Junctions with separating floors

2.60 There are important details in Section 3concerning junctions between wall type 1 andseparating floors.


concrete ground floor slab

Diagram 2-12: Wall type 1 – concreteground floor

SECTION

flexiblecloser

Diagram 2-14: External cavity wall ateaves level

SECTION

roof

mass per unitarea of a least150 kg/m2

ceiling

flexiblecloser

sealedjoints

Diagram 2-13: Wall type 1 – ceiling androof junction

SECTION


E

Wall type 2: Cavity masonry 2.61 The resistance to airborne sounddepends on the mass per unit area of theleaves and on the degree of isolation achieved.The isolation is affected by connections (suchas wall ties and foundations) between the wallleaves and by the cavity width.

Constructions

2.62 Four wall type 2 constructions (types 2.1,2.2, 2.3 and 2.4) are described in this guidance.

2.63 Two of these wall constructions (types2.3 and 2.4) are only suitable when a step inelevation and/or a stagger in plan isincorporated at the separating wall.



Wall ties in separating cavity masonry walls

2.66 The wall ties used to connect the leavesof a cavity masonry wall should be tie type A.

Cavity widths in separating cavity masonrywalls

2.67 Recommended cavity widths areminimum values.

Blocks with voids

2.68 The guidance describes constructionsthat use blocks without voids. For blocks withvoids, seek advice from the manufacturer.

2.69 Wall type 2.1 Two leaves of denseaggregate concrete block with 50 mm cavity,plaster on both room faces (see Diagram 2-15)


• minimum cavity width of 50 mm



Do

a. Do fill and seal all masonry joints withmortar.

b. Do keep the cavity leaves separatebelow ground floor level.

c. Do ensure that any external cavity wallis stopped with a flexible closer at thejunction with the separating wall,unless the cavity is fully filled withmineral wool or expanded polystyrenebeads (seek manufacturer’s advice forother suitable materials).

d. Do control flanking transmission fromwalls and floors connected to theseparating wall as described in theguidance on junctions.

e. Do stagger the position of sockets onopposite sides of the separating wall.

f. Do ensure that flue blocks will notadversely affect the sound insulationand that a suitable finish is used overthe flue blocks (see BS 1289-1:1986and seek manufacturer’s advice).

Do not

a. Do not try and convert a cavityseparating wall to a type 1 (solidmasonry) separating wall byinserting mortar or concrete into thecavity between the two leaves.

b. Do not change to a solid wallconstruction in the roof space as arigid connection between the leaveswill reduce wall performance.

c. Do not build cavity walls off acontinuous solid concrete slab floor.

d. Do not use deep sockets andchases in the separating wall, donot place them back to back.



• 100 mm block leaves


• 225 mm coursing




SECTION


E2.70 Wall type 2.2 Two leaves of lightweightaggregate block with 75 mm cavity, plaster onboth room faces (see Diagram 2-16)




Additional construction: Wall type 2.3 shouldonly be used where there is a step and/orstagger of at least 300 mm.

2.71 Wall type 2.3 Two leaves of lightweightaggregate block with 75 mm cavity andstep/stagger, plasterboard on both room faces(see Diagram 2-17)

• minimum mass per unit areaincluding plasterboard 290 kg/m2

• lightweight aggregate blocks shouldhave a density in the range 1350 to1600 kg/m3


• plasterboard, each sheet of minimummass per unit area 10 kg/m2, on bothroom faces

Note: The composition of the lightweightaggregate blocks contributes to theperformance of this construction with aplasterboard finish. Using denser blocks maynot give an equivalent performance.

Note: Increasing the size of the step or staggerin the separating wall tends to increase theairborne sound insulation






• 225 mm coursing


This is an example only. See Annex A for asimplified method of calculating mass perunit area. Alternatively use manufacturer’sactual figures where these are available. Example of wall type 2.3




• 225 mm coursing

• plasterboard, each sheet of minimummass per unit area 10 kg/m2,on bothroom faces



SECTION


SECTION


EAdditional construction: Wall type 2.4 shouldonly be used in constructions withoutseparating floors and where there is a stepand/or stagger of at least 300 mm.

2.72 Wall type 2.4 Two leaves of aircreteblock with 75mm cavity and step/stagger,plasterboard or plaster on both room faces (seeDiagram 2-18)

• minimum mass per unit areaincluding finish 150 kg/m2


• plasterboard, each sheet of minimummass per unit area 10 kg/m2, on bothroom faces, or

• 13mm plaster on both room faces

Note: Increasing the size of the step or staggerin the separating wall tends to increase theairborne sound insulation.

Junction requirements for walltype 2Junctions with an external cavity wall withmasonry inner leaf



(b) the cavity should be stopped with aflexible closer (for wall types 2.1 and 2.2 seeDiagram 2-19, for wall types 2.3 and 2.4 seeDiagram 2-20) unless the cavity is fully filledwith mineral wool or expanded polystyrenebeads (seek manufacturer’s advice for othersuitable materials).

2.74 The separating wall should be joined tothe inner leaf of the external cavity wall by oneof the following methods:

(a) Bonded. The separating wall should bebonded to the external wall in such a way thatthe separating wall contributes at least 50% ofthe bond at the junction.

(b) Tied. The external wall should abut theseparating wall and be tied to it. See Diagram2-21. Also, see Building Regulation Part A -Structure.

2.75 The masonry inner leaf should have amass per unit area of at least 120 kg/m2

excluding finish. However, there is no minimummass requirement where separating wall type2.1, 2.3 or 2.4 is used.

2.76 Where there is also a separating floorthen the requirement for a minimum mass perunit area of 120 kg/m2 excluding finish shouldalways apply, even when wall type 2.1, 2.3 or2.4 is used.




• 100 mm aircrete block leaves


• 225 mm coursing

• plasterboard, each sheet of minimummass per unit area 10 kg/m2, on bothroom faces



SECTION

cavity stop

Diagram 2-19: Wall type 2.1 and 2.2 –external cavity wall withmasonry inner leaf

PLAN


E




(b) the cavity should be stopped with aflexible closer. See Diagram 2-22.

2.78 Where the inner leaf of an external cavitywall is of framed construction, the framed innerleaf should:

(a) abut the separating wall, and

(b) be tied to it with ties at no more than 300 mm centres vertically.

The wall finish of the inner leaf of the externalwall should be:


(b) two layers of plasterboard where there isa separating floor

(c) each sheet of plasterboard to be ofminimum mass per unit area 10 kg/m2, and


Junctions with an external solid masonrywall





2.81 Internal masonry walls that abut a type 2separating wall should have a mass per unitarea of at least 120 kg/m2 excluding finish.

2.82 Where there is a separating floor, internalmasonry walls should have a mass per unitarea of at least 120 kg/m2 excluding finish.

2.83 When there is no separating floor withseparating wall type 2.3 or 2.4 there is nominimum mass per unit area for internalmasonry walls.


cavity stop

innerleaf

inner leaf

external leaf

at least300mm

Diagram 2-20: Wall type 2.3 and 2.4 –external cavity wall withmasonry inner leaf –stagger

PLAN

cavity stop


tied junction

internalmasonry wall

Diagram 2-21: Wall type 2 – tied junction– external cavity wall withinternal masonry wall

cavity stop


PLAN


EJunctions with internal timber floors

2.84 If the floor joists are to be supported onthe separating wall then they should besupported on hangers and should not be builtin. See Diagram 2-23.


2.85 Internal concrete floors should generallybe built into a type 2 separating wall andcarried through to the cavity face of the leaf.The cavity should not be bridged. See Diagram2-24.


2.86 If the floor joists are to be supported onthe separating wall then they should besupported on hangers and should not be builtin.


Junctions with concrete ground floors

2.88 The ground floor may be a solid slab, laidon the ground, or a suspended concrete floor.A concrete slab floor on the ground should notbe continuous under a type 2 separating wall.See Diagram 2-24.

2.89 A suspended concrete floor should notbe continuous under a type 2 separating wall,and should be carried through to the cavityface of the leaf. The cavity should not bebridged. See Diagram 2-24.


Junctions with ceiling and roof space

2.91 Where a type 2 separating wall is used itshould be continuous to the underside of theroof.

2.92 The junction between the separating walland the roof should be filled with a flexiblecloser which is also suitable as a fire stop. SeeDiagram 2-25.


hanger


SECTION

internalconcrete floor

suspended concreteground floor

concrete slabground floor

groundground

Diagram 2-24: Wall type 2 – internalconcrete floor andconcrete ground floor

SECTION

roof

mass per unitarea of a least150 kg/m2

ceiling

flexiblecloser

sealedjoints

Diagram 2-25: Wall type 2 – ceiling androof junction

SECTION


E2.93 Where the roof or loft space is not ahabitable room and there is a ceiling with aminimum mass per unit area of 10 kg/m2 withsealed joints, then the mass per unit area ofthe separating wall above the ceiling may bereduced to 150 kg/m2, but it should still be acavity wall. See Diagram 2-25.

2.94 If lightweight aggregate blocks of densityless than 1200 kg/m3 are used above ceilinglevel, then one side should be sealed withcement paint or plaster skim.

2.95 Where there is an external cavity wall, thecavity should be closed at eaves level with asuitable flexible material (e.g. mineral wool).See Diagram 2-26.

Note: A rigid connection between the inner andexternal wall leaves should be avoided. If arigid material is used, then it should only berigidly bonded to one leaf.



Wall type 3: Masonry betweenindependent panels2.97 The resistance to airborne sounddepends partly on the type and mass per unitarea of the core, and partly on the isolation andmass per unit area of the independent panels.

Note: Wall type 3 can give high resistance tothe transmission of both airborne sound andimpact sound on the wall.

Construction

2.98 Three wall type 3 constructions (types3.1, 3.2 and 3.3) are described in this guidance.

2.99 The construction consists of either asolid or cavity masonry core wall withindependent panels on both sides. Thesepanels and any frame should not be in contactwith the core wall.




flexiblecloser


SECTION

Do

a. Do fill and seal all masonry jointswith mortar.

b. Do control flanking transmission fromwalls and floors connected to theseparating wall as described in theguidance on junctions.

c. Do fix the panels or the supportingframes to the ceiling and floor only.

d. Do tape and seal all joints.

e. Do ensure that flue blocks will notadversely affect the sound insulationand that a suitable finish is used overthe flue blocks (see BS 1289-1:1986and seek manufacturer’s advice).

Do not

Do not fix, tie or connect the freestanding panels or the frame to themasonry core.


EWall ties in cavity masonry cores

2.102 The wall ties used to connect the leavesof a cavity masonry core should be tie type A.

Cavity widths in separating cavity masonrycores

2.103 Recommended cavity widths areminimum values.

2.104 Independent panels.

These panels should meet the followingspecification:

• minimum mass per unit area of panel(excluding any supporting framework) 20 kg/m2

• panels should consist of either

(a) at least 2 layers of plasterboard withstaggered joints, or

(b) a composite panel consisting of 2sheets of plasterboard separated bya cellular core

• if the panels are not supported on aframe they should be at least 35 mmfrom the masonry core

• if the panels are supported on a framethere should be a gap of at least 10 mmbetween the frame and the masonrycore.

2.105 Wall type 3.1 Solid masonry core (denseaggregate concrete block), independent panelson both room faces (see Diagrams 2-27 and 2-28)

• minimum mass per unit area of core 300 kg/m2

• minimum core width is determined bystructural requirements (see BuildingRegulation Part A - Structure)

• independent panels on both room faces




• 140 mm block core


• 110 mm coursing

• independent panels, each panel ofmass per unit area 20 kg/m2, to betwo sheets of plasterboard with jointsstaggered.


Diagram 2-27: Wall type 3.1 withindependent compositepanels

SECTION

Diagram 2-28: Wall type 3.1 withindependentplasterboard panels

SECTION


E2.106 Wall type 3.2 Solid masonry core(lightweight concrete block), independentpanels on both room faces (see Diagram 2-29)

• minimum mass per unit area of core150 kg/m2

• minimum core width is determinedby structural requirements (seeBuilding Regulation Part A -Structure)

• independent panels on both roomfaces

2.107 Wall type 3.3 Cavity masonry core(brickwork or blockwork), 50 mm cavity,independent panels on both room faces (seeDiagram 2-30)

• the core can be of any mass perunit area


• minimum core width is determinedby structural requirements (seeBuilding Regulation Part A -Structure)

• independent panels on both roomfaces




• 140 mm lightweight block core


• 225 mm coursing

• independent panels, each panel ofmass per unit area 20 kg/m2, to be twosheets of plasterboard joined by acellular core



• two leaves of concrete block

• each leaf at least 100 mm thick


• independent panels, each panel ofmass per unit area 20 kg/m2, to betwo sheets of plasterboard joined bya cellular core


SECTION


SECTION


E




(b) the cavity should be stopped with aflexible closer (see Diagram 2-31) unless thecavity is fully filled with mineral wool orexpanded polystyrene beads (seekmanufacturer’s advice for other suitablematerials).

2.109 Where the inner leaf of an externalcavity wall is masonry:

(a) the inner leaf of the external wall shouldbe bonded or tied to the masonry core.

(b) the inner leaf of the external wall should belined with independent panels in the same manneras the separating walls. See Diagram 2-31.

2.110 Where there is a separating floor themasonry inner leaf of the external wall shouldhave a minimum mass per unit area of at least120 kg/m2 excluding finish.

2.111 Where there is no separating floor and themasonry inner leaf of the external wall is linedwith independent panels in the same manner asthe separating walls, there is no minimum massrequirement on the masonry inner leaf.

2.112 Where there is no separating floor withseparating wall type 3.1 or 3.3, and themasonry inner leaf of the external wall has amass of at least 120 kg/m2 excluding finish,then the inner leaf of the external wall may befinished with plaster or plasterboard ofminimum mass per unit area 10 kg/m2.






2.115 Load bearing framed internal walls shouldbe fixed to the masonry core through a continuouspad of mineral wool. See Diagram 2-32.

2.116 Non-load bearing internal walls shouldbe butted to the independent panels.

2.117 All joints between internal walls andpanels should be sealed with tape or caulkedwith sealant.


2.118 Internal walls that abut a type 3separating wall should not be of masonryconstruction.


2.119 If the floor joists are to be supported onthe separating wall then they should besupported on hangers and should not be builtin. See Diagram 2-33.

2.120 Spaces between the floor joists shouldbe sealed with full depth timber blocking.


cavity stop

independentpanels

independentpanels

Diagram 2-31: Wall type 3 – externalcavity wall with masonryinner leaf

PLAN

cavity stop

mineralwoolpad

internal timber wall sealed joints

Diagram 2-32: Wall type 3 – externalcavity wall with internaltimber wall


EJunctions with internal concrete floors

Wall types 3.1 and 3.2 (solid masonry core)2.121 An internal concrete floor slab may onlybe carried through a solid masonry core if thefloor base has a mass per unit area of at least365 kg/m2. See Diagram 2-34.

Wall type 3.3 (cavity masonry core)2.122 Internal concrete floors should generallybe built into a cavity masonry core and carriedthrough to the cavity face of the leaf. Thecavity should not be bridged.


2.123 If the floor joists are to be supported onthe separating wall then they should besupported on hangers and should not be built in.

2.124 Spaces between the floor joists shouldbe sealed with full depth timber blocking.



2.126 The ground floor may be a solid slab,laid on the ground, or a suspended concretefloor.

Wall type 3.1 and 3.2 (solid masonry core)2.127 A concrete slab floor on the ground maybe continuous under the solid masonry core ofa type 3.1 or 3.2 separating wall.

2.128 A suspended concrete floor may onlypass under the solid masonry core of a type3.1 or 3.2 separating wall if the floor has amass per unit area of at least 365 kg/m2.

2.129 Hollow core concrete plank and concretebeams with infilling block floors should not becontinuous under the solid masonry core of atype 3.1 or 3.2 separating wall.

Wall type 3.3 (cavity masonry core)2.130 A concrete slab floor on the groundshould not be continuous under the cavitymasonry core of a type 3.3 separating wall.

2.131 A suspended concrete floor should notbe continuous under the cavity masonry core ofa type 3.3 separating wall and should becarried through to the cavity face of the leaf.The cavity should not be bridged.



2.133 The masonry core should be continuousto the underside of the roof.

2.134 The junction between the separatingwall and the roof should be filled with a flexiblecloser which is also suitable as a fire stop. SeeDiagram 2-35.

2.135 The junction between the ceiling andindependent panels should be sealed with tapeor caulked with sealant.


hanger


SECTION

concrete floor slabmay be carriedthrough if mass perunit area is at least365 kg/m2

Diagram 2-34: Wall types 3.1 and 3.2 –internal concrete floor

SECTION


E

2.136 Where there is an external cavity wall,the cavity should be closed at eaves level witha suitable flexible material (e.g. mineral wool).See Diagram 2-36.

Note: A rigid connection between the inner andexternal wall leaves should be avoided. If arigid material is used, then it should only berigidly bonded to one leaf.

Wall types 3.1 and 3.2 (solid masonry core)2.137 Where the roof or loft space is not ahabitable room and there is a ceiling with aminimum mass per unit area 10 kg/m2 and withsealed joints, the independent panels may beomitted in the roof space and the mass per unitarea of the separating wall above the ceiling maybe a minimum of 150 kg/m2. See Diagram 2-35.

2.138 If lightweight aggregate blocks ofdensity less than 1200 kg/m3 are used aboveceiling level, then one side should be sealedwith cement paint or plaster skim.

Wall type 3.3 (cavity masonry core)2.139 Where the roof or loft space is not ahabitable room and there is a ceiling with aminimum mass per unit area 10 kg/m2 and withsealed joints, the independent panels may beomitted in the roof space but the cavitymasonry core should be maintained to theunderside of the roof.




roof

ceiling

flexiblecloser

sealedjoints

Diagram 2-35: Wall types 3.1 and 3.2 –ceiling and roof junction

SECTION

flexiblecloser


SECTION


E

Wall type 4: Framed walls withabsorbent material 2.141 In this guidance only a timber framedwall is described. For steel framed walls, seekadvice from the manufacturer.

2.142 The resistance to airborne sounddepends on the mass per unit area of theleaves, the isolation of the frames, and theabsorption in the cavity between the frames.

Construction

2.143 The construction consists of timberframes, with plasterboard linings on roomsurfaces and with absorbent material betweenthe frames.

2.144 One wall type 4 construction (type 4.1)is described in this guidance.



2.147 Wall type 4.1 Double leaf frames withabsorbent material (see Diagram 2-37)

• minimum distance between insidelining faces of 200 mm

• plywood sheathing may be used inthe cavity as necessary forstructural reasons

• each lining to be two or more layersof plasterboard, each sheet ofminimum mass per unit area 10 kg/m2, with staggered joints

• absorbent material to be unfacedmineral wool batts or quilt (whichmay be wire reinforced), minimumdensity 10 kg/m3

• minimum thickness of absorbentmaterial:

(a) 25 mm if suspended in the cavitybetween frames,

(b) 50 mm if fixed to one frame,

(c) 25 mm per batt (or quilt) if one isfixed to each frame.

Note: A masonry core may be used whererequired for structural purposes, but the coreshould be connected to only one frame.


Do

a. Do ensure that where fire stops areneeded in the cavity between framesthat they are either flexible or fixed toonly one frame.

b. Do stagger the position of sockets onopposite sides of the separating wall,and use a similar thickness ofcladding behind the socket box.

c. Do ensure that each layer ofplasterboard is independently fixed tothe stud frame.

d. Do control flanking transmission fromwalls and floors connected to theseparating wall as described in theguidance on junctions.

Do not

a. Where it is necessary to connectthe two leaves together forstructural reasons, do not use ties of greater cross section than40mm x 3mm fixed to the studworkat or just below ceiling level and do not set them at closer than 1.2m centres.

b. Do not locate sockets back toback. A minimum edge to edgestagger of 150mm isrecommended. Do not chaseplasterboard.


E






(b) the cavity should be stopped betweenthe ends of the separating wall and the outerleaf with a flexible closer. See Diagram 2-38.

2.150 The wall finish of the inner leaf of theexternal wall should be:


(b) two layers of plasterboard where thereis a separating floor

(c) each sheet of plasterboard of minimummass per unit area 10 kg/m2, and





socketdetail

socketdetail

socketdetail

(a)

(b)

(c)


PLAN

cavity stops


PLAN


EJunctions with internal framed walls

2.152 There are no restrictions on internalwalls meeting a type 4 separating wall.




2.154 Block the air paths through the wall intothe cavity by using solid timber blockings orcontinuous ring beam or joists.




2.156 Block the air paths through the wall intothe cavity by using solid timber blockings or acontinuous ring beam or joists.



2.158 The ground floor may be a solid slab,laid on the ground, or a suspended concretefloor. A concrete slab floor on the ground maybe continuous under a type 4 separating wall.A suspended concrete floor may only passunder a wall type 4 if the floor has a mass perunit area of at least 365 kg/m2.



2.160 The wall should preferably becontinuous to the underside of the roof.

2.161 The junction between the separatingwall and the roof should be filled with aflexible closer.

2.162 The junction between the ceiling and thewall linings should be sealed with tape orcaulked with sealant.

Where the roof or loft space is not a habitableroom and there is a ceiling with a minimummass per unit area 10 kg/m2 and with sealedjoints, either:

(a) the linings on each frame may bereduced to two layers of plasterboard, eachsheet of minimum mass per unit area10 kg/m2, or

(b) the cavity may be closed at ceiling levelwithout connecting the two frames rigidlytogether and then one frame may be used inthe roof space provided there is a lining of two

layers of plasterboard, each sheet of minimummass per unit area 10 kg/m2, on both sides ofthe frame.

2.163 Where there is an external wall cavity,the cavity should be closed at eaves level witha suitable material.





E

Introduction3.1 This Section gives examples of floortypes which, if built correctly, should achievethe performance standards set out in Section0: Performance - Table 1a.


3.3 The floors are grouped into three maintypes. See Diagram 3-1.

3.4 Floor type 1: Concrete base with ceilingand soft floor covering

The resistance to airborne sound dependsmainly on the mass per unit area of theconcrete base and partly on the mass per unitarea of the ceiling. The soft floor coveringreduces impact sound at source.

3.5 Floor type 2: Concrete base with ceilingand floating floor

The resistance to airborne and impact sounddepends on the mass per unit area of theconcrete base, as well as the mass per unitarea and isolation of the floating layer and theceiling. The floating floor reduces impact soundat source.

3.6 Floor type 2: Floating floor

Floor type 2 requires one of the floating floorsdescribed in this section. The description offloor type 2 contains a suffix (a), (b) or (c)which refers to the floating floor used.

3.7 Floor type 3: Timber frame base withceiling and platform floor

The resistance to airborne and impact sounddepends on the structural floor base and theisolation of the platform floor and the ceiling.The platform floor reduces impact sound atsource.

3.8 Ceiling treatment

Each floor type requires one of the ceilingtreatments described in this section. Thedescription of each floor type contains a suffixA, B or C that refers to the ceiling treatmentused.

3.9 Within each floor type the constructionsare ranked, as far as possible, withconstructions providing better sound insulationgiven first.

Junctions between separatingfloors and other building elements3.10 In order for the floor construction to befully effective, care should be taken to correctlydetail the junctions between the separatingfloor and other elements such as externalwalls, separating walls and floor penetrations.Recommendations are also given for theconstruction of these other elements where it isnecessary to control flanking transmission.Notes and diagrams explain the junction detailsfor each of the separating floor types.

3.11 Table 3.1 indicates the inclusion ofguidance in this document on the junctions thatmay occur between each of the separatingfloor types and various attached buildingelements.

SEPARATING FLOORS (NEW BUILDINGS)

Section 3: Separating floors and associatedflanking constructions for new buildings

soft covering

ceiling

floating floor floating layer resilient layer

platform floor floating layer resilient layer

concrete base

ceiling concrete base

(a) Floor type 1

(b) Floor type 2

independent ceiling timber frame base

(c) Floor type 3

Diagram 3-1: Types of separating floor

SECTION


E

Beam and block floors3.12 For beam and block separating floors,seek advice from the manufacturer.

Mass per unit area of floors3.13 The mass per unit area of a floor isexpressed in kilograms per square metre(kg/m2). The mass per unit area of floors shouldbe obtained from manufacturer’s data orcalculated using the method shown in Annex A.

3.14 The density of the materials used (and onwhich the mass per unit area of the floordepends) is expressed in kilograms per cubicmetre (kg/m3).

3.15 Where appropriate, the mass per unit areaof a bonded screed may be included in thecalculation of the mass per unit area of the floor.

3.16 The mass per unit area of a floatingscreed should not be included in the calculationof the mass per unit area of the floor.

Ceiling treatments3.17 Each floor type should use one of thefollowing three ceiling treatments (A, B or C).See Diagram 3-2.

3.18 The ceiling treatments are ranked, inorder of sound insulation performance from Ato C, with constructions providing higher soundinsulation given first.

Note: Use of a better performing ceiling thanthat described in the guidance should improvethe sound insulation of the floor provided thereis no significant flanking transmission.

3.19 Ceiling treatment A, independent ceilingwith absorbent material

Ceiling treatment A should meet the followingspecification:

• at least 2 layers of plasterboard withstaggered joints

• minimum total mass per unit area ofplasterboard 20 kg/m2

• an absorbent layer of mineral wool(minimum thickness 100 mm, minimumdensity 10 kg/m3) laid in the cavityformed above the ceiling.

The ceiling should be supported by one of thefollowing methods:

• Floor types 1, 2 and 3. Use independentjoists fixed only to the surrounding walls.A clearance of at least 100 mm should beleft between the top of the plasterboardforming the ceiling and the underside ofthe base floor.

• Floor type 3. Use independent joistsfixed to the surrounding walls withadditional support provided by resilienthangers attached directly to the floor. Aclearance of at least 100 mm should beleft between the top of the ceiling joistsand the underside of the base floor.


Separating wall type

Building element attached to separating floor Type 1 Type 2 Type 3

External cavity wall with masonry inner leaf G G G

External cavity wall with timber frame inner leaf G G G

External solid masonry wall N N N

Internal wall - framed G G G

Internal wall - masonry G G N

Floor penetrations G G G

For flats the following may also apply:

Separating wall type 1 - solid masonry G G G

Separating wall type 2 - cavity masonry G G G

Separating wall type 3 - masonry between independent panels G G G

Separating wall type 4 – framed wall with absorbent material N N G

Key: G = guidance available; N = no guidance available (seek specialist advice)

Note: Where any building element functions as a separating element (e.g. a ground floor that is also a separating floor for a basement flat)then the separating element requirements should take precedence.

Table 3.1 Separating floor junctions reference table.


E3.20 Points to watch

3.21 Ceiling treatment B, plasterboard onproprietary resilient bars with absorbent material

Ceiling treatment B should meet the followingspecification:

• single layer of plasterboard, minimummass per unit area of plasterboard 10 kg/m2

• fixed using proprietary resilient metalbars. On concrete floors, these resilientmetal bars should be fixed to timberbattens. For fixing details, seek advicefrom the manufacturer.

• an absorbent layer of mineral wool(minimum density 10 kg/m3) that fills theceiling void.

3.22 Ceiling treatment C, plasterboard ontimber battens or proprietary resilient channelswith absorbent material

Ceiling treatment C should meet the followingspecification:

• single layer of plasterboard, minimummass per unit area 10 kg/m2

• fixed using timber battens or proprietaryresilient channels

• if resilient channels are used, incorporatean absorbent layer of mineral wool(minimum density 10 kg/m3) that fills theceiling void.

Note: Electrical cables give off heat when inuse and special precautions may be requiredwhen they are covered by thermally insulatingmaterials. See BRE BR 262, Thermal Insulation:avoiding risks, section 2.3. Installing recessedlight fittings in ceiling treatments A to C canreduce their resistance to the passage ofairborne and impact sound.

Floor type 1: Concrete base withceiling and soft floor covering3.23 The resistance to airborne sounddepends mainly on the mass per unit area ofthe concrete base and partly on the mass perunit area of the ceiling. The soft floor coveringreduces impact sound at source.

Constructions

3.24 The construction consists of a concretefloor base with a soft floor covering and aceiling.

3.25 Two floor type 1 constructions (types1.1C and 1.2B) are described in this guidancewhich should be combined with the appropriateceiling and soft floor covering.



Do

Do seal the perimeter of theindependent ceiling with tape orsealant.

Do not

Do not create a rigid or directconnection between the independentceiling and the floor base.

Ceiling treatment A (independent joists)

Ceiling treatment B (resilient bars)

Ceiling treatment C (timber battens)

Ceiling treatment C (resilient channels)

Diagram 3-2: Ceiling treatments A , Band C

SECTION


E3.27 Points to watch

3.28 Soft floor covering

The soft floor covering should meet thefollowing specification:

• any resilient material, or material with aresilient base, with an overalluncompressed thickness of at least 4.5 mm, or

• any floor covering with a weightedreduction in impact sound pressure level(∆Lw) of not less than 17 dB whenmeasured in accordance with BS EN ISO140-8:1998 and calculated in accordancewith BS EN ISO 717-2:1997.

3.29 Floor type 1.1C Solid concrete slab (castin-situ or with permanent shuttering), soft floorcovering, ceiling treatment C (see Diagram 3-3)

• minimum mass per unit area of 365 kg/m2

(including shuttering only if it is solidconcrete or metal) and including anybonded screed)

• soft floor covering essential

• ceiling treatment C (or better) essential

3.30 Floor Type 1.2B Concrete planks (solid orhollow), soft floor covering, ceiling treatment B(see Diagram 3-4)

• minimum mass per unit area of planksand any bonded screed of 365 kg/m2

• use a regulating floor screed

• all floor joints fully grouted to ensure airtightness

• soft floor covering essential

• ceiling treatment B (or better) essential

Junction requirements for floortype 1Junctions with an external cavity wall withmasonry inner leaf


(a) the outer leaf of the wall may be ofany construction, and

(b) the cavity should be stopped with aflexible closer (see Diagram 3-5.) ensuringadequate drainage, unless the cavity is fullyfilled with mineral wool or expandedpolystyrene beads (seek manufacturer’s advicefor other suitable materials).

3.32 The masonry inner leaf of an externalcavity wall should have a mass per unit area ofat least 120 kg/m2 excluding finish.


Do

a. Do fix or glue the soft floor covering tothe floor. (N.B. allow for futurereplacement.)

b. Do fill all joints between parts of thefloor to avoid air paths.

c. Do give special attention toworkmanship and detailing at theperimeter and wherever a pipe orduct penetrates the floor in order toreduce flanking transmission and toavoid air paths.

d. Do build a separating concrete floorinto the walls around its entireperimeter where the walls are masonry.

e. Do fill with mortar any gap that mayform between the head of a masonrywall and the underside of theconcrete floor.

f. Do control flanking transmissionfrom walls connected to theseparating floor as described in theguidance on junctions.

Do not

a. Do not allow the floor base to bridgea cavity in a cavity masonry wall.

b. Do not use non-resilient floorfinishes such as ceramic floor tilesand wood block floors that arerigidly connected to the floor base.

Diagram 3-3: Floor type 1.1CFloor type 1.1 with ceilingtreatment C

SECTION

timber batten

Diagram 3-4: Floor type 1.2BFloor type 1.2 with ceilingtreatment B

SECTION


E3.33 The floor base (excluding any screed)should be built into a cavity masonry externalwall and carried through to the cavity face ofthe inner leaf. The cavity should not be bridged.

Floor type 1.2B

3.34 Where floor type 1.2B is used and theplanks are parallel to the external wall the firstjoint should be a minimum of 300 mm from thecavity face of the inner leaf. See Diagram 3-5.

3.35 See details in Section 2 concerning theuse of wall ties in external masonry cavity walls.



(a) the outer leaf of the wall may be ofany construction, and

(b) the cavity should be stopped with aflexible closer.

(c) the wall finish of the inner leaf of theexternal wall should be two layers ofplasterboard, each sheet of plasterboard to beof minimum mass per unit area 10 kg/m2, andall joints should be sealed with tape or caulkedwith sealant.




3.38 There are no restrictions on internalframed walls meeting a type 1 separating floor.


3.39 The floor base should be continuousthrough, or above an internal masonry wall.

3.40 The mass per unit area of any loadbearing internal wall or any internal wall rigidlyconnected to a separating floor should be atleast 120 kg/m2 excluding finish.

Junctions with floor penetrations (excludinggas pipes)

3.41 Pipes and ducts that penetrate a floorseparating habitable rooms in different flatsshould be enclosed for their full height in eachflat. See Diagram 3-6.

3.42 The enclosure should be constructed ofmaterial having a mass per unit area of at least15 kg/m2. Either line the enclosure, or wrap theduct or pipe within the enclosure, with 25 mmunfaced mineral fibre.

3.43 Penetrations through a separating floor byducts and pipes should have fire protection tosatisfy Building Regulation Part B - Fire safety.Fire stopping should be flexible and preventrigid contact between the pipe and floor.

Note: There are requirements for ventilation ofducts at each floor where they contain gaspipes. Gas pipes may be contained in aseparate ventilated duct or they can remainunenclosed. Where a gas service is installed, itshall comply with relevant codes and standardsto ensure safe and satisfactory operation. SeeThe Gas Safety (Installation and Use)Regulations 1998, SI 1998 No.2451.


cavity stop

timber batten

external cavity wall

minimum300 mm

Diagram 3-5: Floor type 1.2B – externalcavity wall with masonryinner leaf

SECTION

lag pipes withmineral wool

seal with tapeor sealant

enclosure

Diagram 3-6: Floor type 1 – floorpenetrations

SECTION


EFor flats where there are separating walls thefollowing may also apply:

Junctions with separating wall type 1 - solidmasonry

Floor type 1.1C

3.44 A separating floor type 1.1C base(excluding any screed) should pass through aseparating wall type 1. See Diagram 3-7.

Floor type 1.2B

3.45 A separating floor type 1.2B base(excluding any screed) should not becontinuous through a separating wall type 1.See Diagram 3-8.

Junctions with separating wall type 2 -cavity masonry

3.46 The mass per unit area of any leaf that issupporting or adjoining the floor should be atleast 120 kg/m2 excluding finish.

3.47 The floor base (excluding any screed)should be carried through to the cavity face ofthe leaf. The wall cavity should not be bridged.See Diagram 3-9.

Floor type 1.2B

3.48 Where floor type 1.2B is used and theplanks are parallel to the separating wall thefirst joint should be a minimum of 300 mm fromthe inner face of the adjacent cavity leaf. SeeDiagram 3-9.

Junctions with separating wall type 3 -masonry between independent panels

Junctions with separating wall type 3.1 and3.2 (solid masonry core)

Floor type 1.1C

3.49 A separating floor type 1.1C base(excluding any screed) should pass throughseparating wall types 3.1 and 3.2. See Diagram3-10.


separating floor type 1.1Ccarried through

floor type 1.1C


Diagram 3-7: Floor type 1.1C –wall type 1

SECTION

floor type 1.2Bfill gapbetween headof wall andunderside of floor


timber batten

Diagram 3-8: Floor type 1.2B –wall type 1

SECTION

separatingfloor type 1carried throughto cavity face

floor type 1.1C floor type 1.2B


timber battenminimum300mm

Diagram 3-9: Floor types 1.1C and 1.2B– wall type 2

SECTION


E

Floor type 1.2B

3.50 A separating floor type 1.2B base(excluding any screed) should not becontinuous through a separating wall type 3.

3.51 Where separating wall type 3.2 is usedwith floor type 1.2B and the planks are parallelto the separating wall the first joint should be aminimum of 300 mm from the centreline of themasonry core.

Junctions with separating wall type 3.3(cavity masonry core)


3.53 The floor base (excluding any screed)should be carried through to the cavity faceof the leaf of the core. The cavity should notbe bridged.

Floor type 1.2B

3.54 Where floor type 1.2B is used and theplanks are parallel to the separating wall thefirst joint should be a minimum of 300 mm fromthe inner face of the adjacent cavity leaf of themasonry core.

Junctions with separating wall type 4 -timber frames with absorbent material


Floor type 2: Concrete base withceiling and floating floor3.56 The resistance to airborne and impactsound depends on the mass per unit area ofthe concrete base, as well as the mass per unitarea and isolation of the floating layer and theceiling. The floating floor reduces impact soundat source.

Constructions

3.57 The construction consists of a concretefloor base with a floating floor and a ceiling.The floating floor consists of a floating layerand a resilient layer.

3.58 Two floor type 2 constructions (types2.1C and 2.2B) are described in this guidance,which should be combined with the appropriateceiling and any one of the three floating flooroptions (a), (b) or (c).


Limitations

3.60 Where resistance to airborne soundonly is required the full construction shouldstill be used.



separating floor type1.1C carried through

separating wall types3.1 and 3.2

floor type 1.1C

Diagram 3-10: Floor type 1.1C – walltypes 3.1 and 3.2

SECTION

Do

a. Do fill all joints between parts of thefloor to avoid air paths.

b. Do give special attention toworkmanship and detailing at theperimeter and wherever a pipe orduct penetrates the floor in order toreduce flanking transmission and toavoid air paths.

c. Do build a separating concrete floorbase into the walls around its entireperimeter where the walls are masonry.

d. Do fill with mortar any gap that mayform between the head of a masonrywall and the underside of theconcrete floor.

e. Do control flanking transmissionfrom walls connected to theseparating floor as described in theguidance on junctions.

Do not

Do not allow the floor base to bridgea cavity in a cavity masonry wall.


E

Floating floors (floating layers andresilient layers)3.62 The floating floor consists of a floatinglayer and resilient layer. See Diagram 3-11.


3.64 Floating floor (a) Timber raft floatinglayer with resilient layer

Floating floor (a) should meet the followingspecification:

• timber raft of board material (with bondededges e.g. tongued and grooved) ofminimum mass per unit area 12 kg/m2,fixed to 45 mm x 45 mm battens

• timber raft to be laid loose on theresilient layer, battens should not be laidalong any joints in the resilient layer

• resilient layer of mineral wool with density36 kg/m3 and minimum thickness 25 mm.The resilient layer may be paper faced onthe underside

3.65 Floating floor (b) Sand cement screedfloating layer with resilient layer

Floating floor (b) should meet the followingspecification:

• floating layer of 65 mm sand cementscreed or a suitable proprietary screedproduct with a mass per unit area of atleast 80 kg/m2. Ensure that the resilientlayer is protected while the screed isbeing laid. A 20 – 50 mm wire mesh maybe used for this purpose.

• resilient layer consisting of either:

a) a layer of mineral wool of minimumthickness 25 mm with density36 kg/m3, paper faced on the upperside to prevent the screed enteringthe resilient layer, or

b) an alternative type of resilient layerwhich meets the following tworequirements:

(i) maximum dynamic stiffness(measured according to BS EN29052-1:1992) of 15 MN/m3, and

(ii) minimum thickness of 5 mm underthe load specified in themeasurement procedure of BS EN29052-1:1992, 1.8 kPa to 2.1 kPa.

Note: For proprietary screed products, seekadvice from the manufacturer.

3.66 Floating floor (c) Performance basedapproach

Floating floor (c) should meet the followingspecification:

• rigid boarding above a resilient and/ordamping layer(s), with

• weighted reduction in impact soundpressure level (∆Lw) of not less than 29 dB when measured according to BS EN ISO 140-8:1998 and ratedaccording to BS EN ISO 717-2:1997. (See Annex B: Supplementary guidanceon acoustic measurement standards.).The performance value ∆Lw should beachieved when the floating floor is bothloaded and unloaded as described in BSEN ISO 140-8:1998 for category IIsystems.

Note: For details on the performance andinstallation of proprietary floating floors, seekadvice from the manufacturer.


Do

a. Do leave a small gap (as advised bythe manufacturer) between the floatinglayer and wall at all room edges andfill with a flexible sealant.

b. Do leave a small gap (approx. 5 mm)between skirting and floating layer andfill with a flexible sealant.

c. Do lay resilient materials in rolls orsheets with lapped joints or with jointstightly butted and taped.

d. Do use paper facing on the upper sideof fibrous materials to prevent screedentering the resilient layer.

Do not

a. Do not bridge between the floatinglayer and the base or surroundingwalls (e.g. with services or fixingsthat penetrate the resilient layer).

b. Do not let the floating screed createa bridge (for example through a gapin the resilient layer) to the concretefloor base or surrounding walls.

Floating floor (a)

Floating floor (b)

Diagram 3-11: Floating floors (a) and (b)

SECTION


E3.67 Floor type 2.1C Solid concrete slab (castin-situ or with permanent shuttering), floatingfloor, ceiling treatment C (see Diagrams 3-12and 3-13)

• minimum mass per unit area of 300 kg/m2

(including shuttering only if it is solidconcrete or metal), and any bonded screed

• regulating floor screed optional

• floating floor (a), (b) or (c) essential

• ceiling treatment C (or better) essential

3.68 Floor type 2.2B Concrete planks (solid orhollow), floating floor, ceiling treatment B (seeDiagrams 3-14 and 3-15)

• minimum mass per unit area of planksand any bonded screed of 300 kg/m2

• use a regulating floor screed

• all floor joints fully grouted to ensure airtightness

• floating floor (a), (b) or (c) essential

• ceiling treatment B (or better) essential


Diagram 3-12: Floor type 2.1C(a)Floor type 2.1 withceiling treatment C andfloating floor (a)

SECTION

Diagram 3-13: Floor type 2.1C(b) Floor type 2.1 withceiling treatment C andfloating floor (b)

SECTION

timber batten

Diagram 3-14: Floor type 2.2B(a)Floor type 2.2 withceiling treatment B andfloating floor (a)

SECTION

timber batten

Diagram 3-15: Floor type 2.2B(b)Floor type 2.2 with ceiling treatment B andfloating floor (b)

SECTION


E




(b) the cavity should be stopped with aflexible closer (see Diagram 3-16) ensuringadequate drainage, unless the cavity is fullyfilled with mineral wool or expandedpolystyrene beads (seek manufacturer’s advicefor other suitable materials).

3.70 The masonry inner leaf of an externalcavity wall should have a mass per unit area ofat least 120 kg/m2 excluding finish.

3.71 The floor base (excluding any screed)should be built into a cavity masonry externalwall and carried through to the cavity face ofthe inner leaf. The cavity should not be bridged.

Floor 2.2B

3.72 Where floor 2.2B is used and the planksare parallel to the external wall the first jointshould be a minimum of 300 mm from thecavity face of the inner leaf. See Diagram 3-16.





(b) the cavity should be stopped with aflexible closer

(c) the wall finish of the inner leaf of theexternal wall should be two layers of plasterboard,each sheet of plasterboard to be of minimummass per unit area 10 kg/m2, and all joints shouldbe sealed with tape or caulked with sealant.




3.76 There are no restrictions on internalframed walls meeting a type 2 separating floor.


3.77 The floor base should be continuousthrough, or above an internal masonry wall.

3.78 The mass per unit area of any loadbearing internal wall or any internal wall rigidlyconnected to a separating floor should be atleast 120 kg/m2 excluding finish.

Junctions with floor penetrations (excludinggas pipes)

3.79 Pipes and ducts that penetrate a floorseparating habitable rooms in different flatsshould be enclosed for their full height in eachflat. See Diagram 3-17.

3.80 The enclosure should be constructed ofmaterial having a mass per unit area of at least15 kg/m2. Either line the enclosure, or wrap theduct or pipe within the enclosure, with 25 mmunfaced mineral wool.

3.81 Leave a small gap (approx. 5 mm)between the enclosure and floating layer andseal with sealant or neoprene. Where floatingfloor (a) or (b) is used the enclosure may godown to the floor base, but ensure that theenclosure is isolated from the floating layer.

3.82 Penetrations through a separating floor byducts and pipes should have fire protection tosatisfy Building Regulation Part B - Fire safety.Fire stopping should be flexible and also preventrigid contact between the pipe and floor.



cavity stop

external cavity wall

timber batten

fill small gap withflexible seal

minimum300 mm

Diagram 3-16: Floor type 2 – externalcavity wall with masonryinternal leaf

SECTION


E

For flats where there are separating walls thefollowing may also apply:

Junctions with a separating wall type 1 -solid masonry

Floor type 2.1C

3.83 A separating floor type 2.1C base(excluding any screed) should pass through aseparating wall type 1.

Floor type 2.2B

3.84 A separating floor type 2.2B base(excluding any screed) should not becontinuous through a separating wall type 1.See Diagram 3-18.

Junctions with a separating wall type 2 -cavity masonry

3.85 The floor base (excluding any screed)should be carried through to the cavity face ofthe leaf. The cavity should not be bridged.

Floor type 2.2B

3.86 Where floor type 2.2B is used and theplanks are parallel to the separating wall thefirst joint should be a minimum of 300 mm fromthe cavity face of the leaf.

Junctions with a separating wall type 3 -masonry between independent panels

Junctions with separating wall type 3.1 and3.2 (solid masonry core)

Floor type 2.1C

3.87 A separating floor type 2.1C base(excluding any screed) should pass throughseparating wall types 3.1 and 3.2. See Diagram3-19.

Floor type 2.2B

3.88 A separating floor type 2.2B base(excluding any screed) should not becontinuous through a separating wall type 3.

3.89 Where separating wall type 3.2 is usedwith floor type 2.2B and the planks are parallelto the separating wall the first joint should be aminimum of 300 mm from the centreline of themasonry core.



fill small gapwith flexibleseal


enclosure


SECTION


floor 2.2B(a)

timber batten

floor 2.2B(b)


Diagram 3-18: Floor types 2.2B(a) and2.2B(b) – wall type 1

SECTION


floor2.1C(a)

floor2.1C(b)

separating wall types3.1 and 3.2

Diagram 3-19: Floor type 2.1C – walltypes 3.1 and 3.2

SECTION


EJunctions with separating wall type 3.3(cavity masonry core)


3.91 The floor base (excluding any screed)should be carried through to the cavity face ofthe leaf of the core. The cavity should not bebridged.

Floor type 2.2B

3.92 Where floor type 2.2B is used and theplanks are parallel to the separating wall thefirst joint should be a minimum of 300 mm fromthe inner face of the adjacent cavity leaf of themasonry core.

Junctions with separating wall type 4 -timber frames with absorbent material


Floor type 3: Timber frame basewith ceiling and platform floor 3.94 The resistance to airborne and impactsound depends on the structural floor base andthe isolation of the platform floor and theceiling. The platform floor reduces impactsound at source.

Construction

3.95 The construction consists of a timberframe structural floor base with a deck,platform floor and ceiling treatment A. Theplatform floor consists of a floating layer and aresilient layer.

3.96 One floor type 3 construction (type 3.1A)is described in this guidance.


Limitations

3.98 Where resistance to airborne sound only isrequired the full construction should still be used.


3.100 Floor type 3.1A Timber frame basewith ceiling treatment A and platform floor (seeDiagram 3-20)

• timber joists with a deck

• the deck should be of any suitablematerial with a minimum mass per unitarea of 20 kg/m2

• platform floor (including resilient layer)essential

• ceiling treatment A essential


Do

a. Do give special attention toworkmanship and detailing at theperimeter and wherever the floor ispenetrated, to reduce flankingtransmission and to avoid air paths.

b. Do control flanking transmission fromwalls connected to the separating flooras described in the guidance onjunctions.

Platform floor

c. Do use the correct density of resilientlayer and ensure it can carry theanticipated load.

d. Do use an expanded or extrudedpolystyrene strip (or similar resilientmaterial) around the perimeter which isapprox. 4mm higher than the uppersurface of the floating layer to ensurethat during construction a gap ismaintained between the wall and thefloating layer. This gap may be filledwith a flexible sealant.

e. Do lay resilient materials in sheets withjoints tightly butted and taped.

Do not

Do not bridge between the floatinglayer and the base or surroundingwalls (e.g. with services or fixingsthat penetrate the resilient layer).

at least100 mm

Diagram 3-20: Floor type 3.1A

SECTION


E3.101 Platform floor

The floating layer should be:

• a minimum of two layers of boardmaterial

• minimum total mass per unit area 25 kg/m2

• each layer of minimum thickness 8 mm

• fixed together (e.g. spot bonded with aresilient adhesive or glued/screwed) withjoints staggered.

The floating layer should be laid loose on aresilient layer.

3.102 Resilient layer

The resilient layer specification is:

• mineral wool, minimum thickness 25 mm,density 60 to 100 kg/m3

• the mineral wool may be paper faced onthe underside.

Note: The lower figure of density for the resilientlayer gives a higher resistance to impact soundbut a ‘softer’ floor. In such cases additionalsupport can be provided around the perimeter ofthe floor by using a timber batten with a foamstrip along the top attached to the wall.




(b) the cavity should be stopped with aflexible closer unless the cavity is fully filledwith mineral wool or expanded polystyrene

beads (seek manufacturer’s advice for othersuitable materials).

3.104 The masonry inner leaf of a cavitywall should be lined with an independent panelas described for wall type 3.

3.105 The ceiling should be taken throughto the masonry. The junction between theceiling and the independent panel should besealed with tape or caulked with sealant.

3.106 Use any normal method ofconnecting floor base to wall but block airpaths between floor and wall cavities.

3.107 Where the mass per unit area of theinner leaf is greater than 375 kg/m2 theindependent panels are not required.





(b) the cavity should be stopped with aflexible closer.

3.110 The wall finish of the inner leaf of theexternal wall should be:

(a) two layers of plasterboard,

(b) each sheet of plasterboard of minimummass per unit area 10 kg/m2, and

(c) all joints should be sealed with tape orcaulked with sealant.

3.111 Use any normal method ofconnecting floor base to wall. Where the joistsare at right angles to the wall, spaces betweenthe floor joists should be sealed with full depthtimber blocking.

3.112 The junction between the ceiling andwall lining should be sealed with tape orcaulked with sealant.


3.113 No guidance available (seekspecialist advice).


3.114 Where the joists are at right angles tothe wall, spaces between the floor joists shouldbe sealed with full depth timber blocking.

3.115 The junction between the ceiling andthe internal framed wall should be sealed withtape or caulked with sealant.


3.116 No guidance available (seekspecialist advice).


Example 1

• 18 mm timber or wood based board

• tongued and grooved edges and gluedjoints

• spot bonded to a substrate of 19 mmplasterboard with joints staggered

• minimum total mass per unit area25 kg/m2

Example 2

• two layers of cement bonded particleboard with staggered joints

• total thickness 24 mm

• boards glued and screwed together

• minimum total mass per unit area 25 kg/m2


EJunctions with floor penetrations (excludinggas pipes)

3.117 Pipes and ducts that penetrate afloor separating habitable rooms in differentflats should be enclosed for their full height ineach flat. See Diagram 3-21.

3.118 The enclosure should be constructedof material having a mass per unit area of atleast 15 kg/m2. Either line the enclosure, orwrap the duct or pipe within the enclosure,with 25 mm unfaced mineral wool.

3.119 Leave a small gap (approx. 5 mm)between enclosure and floating layer and sealwith sealant or neoprene. The enclosure maygo down to the floor base, but ensure that theenclosure is isolated from the floating layer.

3.120 Penetrations through a separatingfloor by ducts and pipes should have fireprotection to satisfy Building Regulation Part B- Fire safety. Fire stopping should be flexibleand also prevent rigid contact between thepipe and floor.


For flats where there are separating walls thefollowing may also apply:

Junctions with a separating wall type 1 -solid masonry

3.121 If floor joists are to be supported onthe separating wall then they should besupported on hangers and should not be builtin. See Diagram 3-22.

3.122 The junction between the ceiling andwall should be sealed with tape or caulkedwith sealant.

Junctions with a separating wall type 2 -cavity masonry

3.123 If floor joists are to be supported onthe separating wall then they should besupported on hangers and should not be builtin. See Diagram 3-23.

3.124 The inner leaf of a cavity wall shouldbe lined with an independent panel asdescribed in wall type 3.


3.126 Where the mass per unit area of theinner leaf is greater than 375 kg/m2 theindependent panels are not required.


fill smallgap withflexibleseal

seal withtape orsealant


enclosure


SECTION

hanger



Diagram 3-22: Floor type 3 – wall type 1

SECTION


E

Junctions with a separating wall type 3 -masonry between independent panels

3.127 If floor joists are to be supported onthe separating wall then they should besupported on hangers and should not be built in.


Junctions with a separating wall type 4 -timber frames with absorbent material

3.129 Where the joists are at right angles tothe wall, spaces between the floor joists shouldbe sealed with full depth timber blocking.

3.130 The junction of the ceiling and walllining should be sealed with tape or caulkedwith sealant.


hanger



Diagram 3-23: Floor type 3 – wall type 2

SECTION


E

Introduction4.1 This Section gives guidance on dwelling-houses and flats formed by material change ofuse. For rooms for residential purposes formedby material change of use see Section 6.

4.2 It may be that an existing wall, floor orstair in a building that is to undergo a materialchange of use will achieve the performancestandards set out in Section 0: Performance -Table 1a without the need for remedial work.This would be the case if the construction wasgenerally similar (including flankingconstructions) to one of the constructions inSections 2 and 3 (e.g. concerning the massrequirement, the structure under considerationshould be within 15% of the mass per unit areaof a construction listed in the relevant section).

4.3 In other circumstances it may be possibleto use the guidance in Section 2 or 3 (includingflanking constructions) to determine theappropriate remedial treatment which will resultin the construction achieving the performancestandards in Section 0: Performance - Table 1a.

4.4 For situations where it is uncertainwhether the existing construction achieves theperformance standards set out in Section 0:Performance - Table 1a, this section describesone wall treatment, two floor treatments andone stair treatment as shown in Diagram 4-1.These constructions can be used to increasethe sound insulation.


4.6 Wall treatment 1 Independent panel(s)with absorbent material

The resistance to airborne sound depends onthe form of existing construction, the mass ofthe independent panel(s), the isolation of thepanel(s) and the absorbent material.

4.7 Floor treatment 1 Independent ceilingwith absorbent material

The resistance to airborne and impact sounddepends on the combined mass of the existingfloor and the independent ceiling, theabsorbent material, the isolation of theindependent ceiling and the airtightness of thewhole construction.

4.8 Floor treatment 2 Platform floor withabsorbent material

The resistance to airborne and impact sounddepends on the total mass of the floor, theeffectiveness of the resilient layer and theabsorbent material.

4.9 Stair treatment 1 Stair covering andindependent ceiling with absorbent material

To be used where a timber stair performs aseparating function. The resistance to airbornesound depends mainly on the mass of the stair,the mass and isolation of any independentceiling and the airtightness of any cupboard orenclosure under the stairs. The stair coveringreduces impact sound at source.

4.10 In all cases it may be necessary tocontrol flanking transmission in order toachieve the performance standards set out inSection 0: Performance - Table 1a. See Section 4: Junction requirements for materialchange of use.

4.11 Special attention needs to be given tosituations where flanking walls or floors arecontinuous across separating walls or floors asa result of the conversion work. In suchinstances additional treatments may berequired to control flanking transmission alongthese continuous elements. Specialist advicemay be needed.

4.12 Significant differences may frequentlyoccur between the construction and layout ofeach converted unit in a development. Buildingcontrol bodies should have regard to theguidance in Section 1 when deciding on theapplication of pre-completion testing tomaterial change of use.

4.13 For some historic buildings undergoing amaterial change of use, it may not be practicalto improve the sound insulation to theperformance standards set out in Section 0:Performance - Table 1a. In such cases refer toSection 0: Performance, paragraph 0.7.

4.14 Wall and floor treatments will imposeadditional loads on the existing structure. Thestructure should be assessed to ensure thatthe additional loading can be carried safely,with appropriate strengthening applied wherenecessary.

4.15 Floor or wall penetrations, such as ductsor pipes, passing through separating elementsin conversions can reduce the level of soundinsulation. Guidance on the treatment of floorpenetrations is given below.

Section 4: Dwelling-houses and flats formedby material change of use

DWELLING-HOUSES AND FLATS FORMED BY MATERIAL CHANGE OF USE


E

Work to existing construction4.16 Before a floor treatment is appliedappropriate remedial work to the existingconstruction should be undertaken asdescribed in paragraphs 4.17 and 4.18.

4.17 If the existing floor is timber then gaps infloor boarding should be sealed by overlayingwith hardboard or filled with sealant.

(a) Where floor boards are to be replaced,boarding should have a minimum thickness of12 mm, and mineral wool (minimum thickness100 mm, minimum density 10 kg/m3) should belaid between the joists in the floor cavity.

(b) If the existing floor is concrete and themass per unit area of the concrete floor is lessthan 300 kg/m2, or is unknown, then the massof the floor should be increased to at least300 kg/m2. Any air gaps through a concretefloor should be sealed. A regulating screed mayalso be required.

(c) If there is an existing lath and plasterceiling it should be retained as long as itsatisfies Building Regulation Part B - Fire safety.

d) Where the existing ceiling is not lath andplaster it should be upgraded as necessary toprovide at least two layers of plasterboardwith joints staggered, total mass per unit area20 kg/m2.

4.18 Extensive remedial work to reduceflanking transmission may also be necessary toachieve the performance standards set out inSection 0: Performance - Table 1a. This mayinvolve wall linings, see Section 4: Junctionrequirements for material change of use,paragraphs 4.43 and 4.44.

Corridor walls and doors4.19 The separating walls described in thissection should be used between dwelling-houses,or flats formed by material change of use andcorridors in order to control flanking transmissionand to provide the required sound insulation.However, it is likely that the sound insulation willbe reduced by the presence of a door.

4.20 Ensure that any door has good perimetersealing (including the threshold where practical)and a minimum mass per unit area of 25 kg/m2

or a minimum sound reduction index of 29 dBRw (measured according to BS EN ISO 140-3:1995 and rated according to BS EN ISO 717-1:1997). The door should also satisfy theRequirements of Building Regulation Part B -Fire safety.

4.21 Noisy parts of the building shouldpreferably have a lobby, double door or highperformance doorset to contain the noise. Wherethis is not possible, nearby flats should havesimilar protection. However, there should be asufficient number of them that are suitable fordisabled access, see Building Regulation Part M- Access and facilities for disabled people.


Wall treatment 1

Floor treatment 1

Floor treatment 2

Stair treatment 1

Diagram 4-1: Treatments for materialchange of use


E

Wall treatment 1: Independentpanel(s) with absorbent material4.22 The resistance to airborne sounddepends on the form of existing construction,the mass of independent panel(s), the isolationof the panel(s) and the absorbent material.

Construction

4.23 The independent panel may be used onone side of the existing wall only where theexisting wall is masonry, and has a thickness ofat least 100 mm and is plastered on bothfaces. With other types of existing wall theindependent panels should be built on bothsides.

4.24 Independent panel(s) with absorbentmaterial (see Diagram 4-2)

• minimum mass per unit area of panel(excluding any supporting framework)20 kg/m2

• each panel should consist of at least 2layers of plasterboard with staggered joints

• if the panels are free-standing they shouldbe at least 25 mm from masonry core

• if the panels are supported on a framethere should be a gap of at least 10 mmbetween the frame and the face of theexisting wall

• mineral wool, minimum density 10 kg/m3

and minimum thickness 35 mm, in thecavity between the panel and theexisting wall



Do

a. Do ensure that the independent paneland its supporting frame are not incontact with the existing wall.

b. Do seal the perimeter of theindependent panel with tape or sealant.

Do not

Do not tightly compress theabsorbent material as this maybridge the cavity.

minimumdistanceis 10mm

mineralwool

frame

mineralwool

existingwall

existingwall

2 layersplasterboard

free-standingpanel

minimum distance is 35 mm

minimum distance is 35 mm

Diagram 4-2: Wall treatment 1

PLAN


E

Floor treatment 1: Independentceiling with absorbent material4.26 The resistance to airborne and impactsound depends on the combined mass of theexisting floor and the independent ceiling, theabsorbent material, the isolation of theindependent ceiling and the airtightness of thewhole construction.

4.27 Independent ceiling with absorbentmaterial (see Diagram 4-3)

• at least 2 layers of plasterboard withstaggered joints, minimum total mass perunit area 20 kg/m2

• an absorbent layer of mineral wool laidon the ceiling, minimum thickness 100 mm, minimum density 10 kg/m3.

The ceiling should be supported by one of thefollowing methods:

• independent joists fixed only to thesurrounding walls. A clearance of at least25 mm should be left between the top ofthe independent ceiling joists and theunderside of the existing floorconstruction, or

• independent joists fixed to thesurrounding walls with additional supportprovided by resilient hangers attacheddirectly to the existing floor base.

Note: This construction involves a separationof at least 125 mm between the upper surfaceof the independent ceiling and the underside ofthe existing floor construction. However,structural considerations determining the sizeof ceiling joists will often result in greaterseparation. Care should be taken at the designstage to ensure that adequate ceiling height isavailable in all rooms to be treated.

4.28 Where a window head is near to theexisting ceiling, the new independent ceilingmay be raised to form a pelmet recess. SeeDiagram 4-4.

4.29 For the junction detail between floortreatment 1 and wall treatment 1, see Diagram4-5.



Do

a. Do remember to apply appropriateremedial work to the existingconstruction.

b. Do seal the perimeter of theindependent ceiling with tape or sealant.

Do not

a. Do not create a rigid or directconnection between the independentceiling and the floor base.

b. Do not tightly compress theabsorbent material as this maybridge the cavity.

existing floor

at least 25mmclearance

independentceiling joist

mineralwool

existing ceiling upgraded to 20 kg/m2

at least125 mm

Diagram 4-3: Floor treatment 1

SECTION

original ceiling level

independent ceiling level

pelmetrecess

Diagram 4-4: Floor treatment 1 - highwindow head detail

SECTION


E

Floor treatment 2: Platform floorwith absorbent material4.31 The resistance to airborne and impactsound depends on the total mass of the floor,the effectiveness of the resilient layer and theabsorbent material.

4.32 Platform floor with absorbent material(see Diagram 4-6)

Where this treatment is used to improve anexisting timber floor, a layer of mineral wool(minimum thickness 100 mm, minimum density10 kg/m3) should be laid between the joists inthe floor cavity.

The floating layer should be:

• a minimum of two layers of boardmaterial

• minimum total mass per unit area25 kg/m2

• each layer of minimum thickness 8mm

• fixed together (e.g. spot bonded orglued/screwed) with joints staggered

The floating layer should be laid loose on aresilient layer. The resilient layer specificationis:

• mineral wool, minimum thickness 25 mm,density 60 to 100 kg/m3

• the mineral wool may be paper faced onthe underside.

Note: The lower figure of density for theresilient layer gives the best insulation but a‘softer’ floor. In such cases additional supportcan be provided around the perimeter of thefloor by using a timber batten with a foam stripalong the top attached to the wall.

4.33 For the junction detail between floortreatment 2 and wall treatment 1, seeDiagram 4-7.



Diagram 4-5: Floor treatment 1 - walltreatment 1

SECTION

Do

a. Do remember to apply appropriateremedial work to the existingconstruction.

b. Do use the correct density of resilientlayer and ensure it can carry theanticipated load.

c. Do allow for movement of materialse.g. expansion of chipboard afterlaying (to maintain isolation).

d. Do carry the resilient layer up at allroom edges to isolate the floatinglayer from the wall surface.

e. Do leave a small gap (approx. 5 mm)between skirting and floating layer andfill with a flexible sealant.

f. Do lay resilient materials in sheets withjoints tightly butted and taped.

g. Do seal the perimeter of any newceiling with tape or sealant.

Do not

Do not bridge between the floatinglayer and the base or surroundingwalls (e.g. with services or fixingsthat penetrate the resilient layer).

floating layer

existing ceiling upgraded to 20 kg/m2

mineral wool

resilient layer

Diagram 4-6: Floor treatment 2

SECTION


E

Stair treatment: Stair covering andindependent ceiling withabsorbent material4.35 Stairs are subject to the same soundinsulation requirements as floors where theyperform a separating function.

4.36 The resistance to airborne sounddepends mainly on the mass of the stair, themass and isolation of any independent ceilingand the airtightness of any cupboard orenclosure under the stairs. The stair coveringreduces impact sound at source.

4.37 Stair covering and independent ceilingwith absorbent material

Lay soft covering of at least 6mm thickness overthe stair treads. Ensure it is securely fixed (e.g.glued) so it does not become a safety hazard.

If there is a cupboard under all, or part, of thestair:

(a) line the underside of the stair within thecupboard with plasterboard of minimum massper unit area 10 kg/m2 and an absorbent layerof mineral wool, (minimum density 10 kg/m3),within the space above the lining, and

(b) build cupboard walls from two layers ofplasterboard (or equivalent), each sheet ofminimum mass per unit area 10 kg/m2, and

(c) use a small, heavy, well fitted door forthe cupboard.

Where there is no cupboard under the stairconstruct an independent ceiling below thestair (see Floor treatment 1).

4.38 For fire protection where a staircaseperforms a separating function refer to BuildingRegulation Part B - Fire safety.

Junction requirements for materialchange of use Junctions with abutting construction

4.39 For floating floors, carry the resilient layerup at all room edges to isolate the floatinglayer from the wall surface.

4.40 For floating floors, leave a small gap(approx. 5 mm) between the skirting andfloating layer and fill with a flexible sealant.

4.41 The perimeter of any new ceiling shouldbe sealed with tape or caulked with sealant.

4.42 Relevant junction details are shown inDiagrams 4-5 and 4-7.

Junctions with external or load bearing walls

4.43 Where there is significant flankingtransmission along adjoining walls thenimproved sound insulation can be achieved bylining all adjoining masonry walls with either

(a) an independent layer of plasterboard, or

(b) a laminate of plasterboard and mineralwool. For other drylining laminates, seek advicefrom the manufacturer.

4.44 Where the adjoining masonry wall has amass per unit area greater than 375 kg/m2 thensuch lining may not be necessary, as it may notgive a significant improvement.

Note: Specialist advice may be needed on thediagnosis and control of flanking transmission.


Diagram 4-7: Floor treatment 2 - walltreatment 1

SECTION

soft covering

plasterboard

mineral wool

fixing batten

Diagram 4-8: Stair treatment

SECTION


EJunctions with floor penetrations

4.45 Piped services (excluding gas pipes) andducts which pass through separating floors inconversions should be surrounded with soundabsorbent material for their full height andenclosed in a duct above and below the floor.

Construction

4.46 Pipes and ducts that penetrate a floorseparating habitable rooms in different flats shouldbe enclosed for their full height in each flat.

4.47 The enclosure should be constructed ofmaterial having a mass per unit area of at least15 kg/m2.

4.48 Either line the enclosure, or wrap theduct or pipe within the enclosure, with 25 mmunfaced mineral wool.

4.49 The enclosure may go down to the floorbase if floor treatment 2 is used but ensureisolation from the floating layer.

4.50 Penetrations through a separating floor byducts and pipes should have fire protection tosatisfy Building Regulation Part B - Fire safety.Fire stopping should be flexible and also preventrigid contact between the pipe and floor.

Note: There are requirements for ventilation ofducts at each floor where they contain gaspipes. Gas pipes may be contained in aseparate ventilated duct or they can remainunducted. Where a gas service is installed, itshall comply with relevant codes and standardsto ensure safe and satisfactory operation. SeeThe Gas Safety (Installation and Use)Regulations 1998, SI 1998 No.2451.


Do

a. Do seal the joint between casings andceiling with tape or sealant.

b. Do leave a nominal gap (approx.5 mm) between the casing and anyfloating layer and fill with sealant.


enclosure

Diagram 4-9: Floor penetrations

SECTION


E

Introduction5.1 This Section gives examples of internalwall and floor constructions that meet thelaboratory sound insulation values set out inSection 0: Performance - Table 2.

5.2 These constructions have been designedto give insulation against airborne sound. Forinternal floors, insulation against impact soundcould be improved by adding a soft covering(e.g. carpet).

5.3 They are grouped in four main types asshown below.

5.4 Internal wall type A or B: Timber ormetal frame

The resistance to airborne sound depends onthe mass per unit area of the leaves, the cavitywidth, frame material and the absorption in thecavity between the leaves.

5.5 Internal wall type C or D: Concrete oraircrete block

The resistance to airborne sound dependsmainly on the mass per unit area of the wall.

5.6 Internal floor type A or B: Concreteplanks or concrete beams with infilling blocks

The resistance to airborne sound depends onthe mass per unit area of the concrete base orconcrete beams and infilling blocks. A softcovering will reduce impact sound at source.

5.7 Internal floor type C: Timber or metaljoist

The resistance to airborne sound depends onthe structural floor base, the ceiling and theabsorbent material. A soft covering will reduceimpact sound at source.

5.8 For both internal walls and internal floorsthe constructions are ranked, as far aspossible, with constructions giving bettersound insulation given first.

Doors5.9 Lightweight doors with poor perimetersealing provide a lower standard of soundinsulation than walls. This will reduce theeffective sound insulation of the internal wall.Ways of improving sound insulation includeensuring that there is good perimeter sealing orby using a doorset.

5.10 See Building Regulation Part F -Ventilation and Part J - Combustion appliancesand fuel storage systems.

Layout5.11 If the stair is not enclosed, then thepotential sound insulation of the internal floorwill not be achieved, nevertheless, the internalfloor should still satisfy Requirement E2.

5.12 It is good practice to consider the layout ofrooms at the design stage to avoid placing noisesensitive rooms next to rooms in which noise isgenerated. Guidance on layout is provided in BS 8233:1999 Sound Insulation and NoiseReduction for Buildings - Code of Practice.

Junction requirements for internalwalls5.13 Section 3: Separating Floors containsimportant guidance on junctions of separatingfloors with internal walls.

5.14 Fill all gaps around internal walls to avoidair paths between rooms.

Junction requirements for internalfloors5.15 Section 2: Separating Walls containsimportant guidance on junctions of separatingwalls with internal floors.

5.16 Fill all gaps around internal floors toavoid air paths between rooms.

5.17 Internal wall type A: Timber or metalframes with plasterboard linings on each sideof frame (see Diagram 5-1)

• each lining to be two or more layers ofplasterboard, each sheet of minimummass per unit area 10 kg/m2

• linings fixed to timber frame with aminimum distance between linings of 75 mm, or metal frame with a minimumdistance between linings of 45 mm

• all joints well sealed

Section 5: Internal walls and floors fornew buildings

INTERNAL WALLS AND FLOORS (NEW BUILDINGS)


E

5.18 Internal wall type B: Timber or metalframes with plasterboard linings on each side offrame and absorbent material (see Diagram 5-2)

• single layer of plasterboard of minimummass per unit area 10 kg/m2

• linings fixed to timber frame with aminimum distance between linings of 75 mm, or metal frame with a minimumdistance between linings of 45 mm

• an absorbent layer of unfaced mineralwool batts or quilt (minimum thickness 25 mm, minimum density 10 kg/m3) whichmay be wire reinforced, suspended in thecavity


5.19 Internal wall type C: Concrete blockwall, plaster or plasterboard finish on bothsides (see Diagram 5-3)

• minimum mass per unit area, excludingfinish 120 kg/m2


• plaster or plasterboard finish on bothsides

5.20 Internal wall type D: Aircrete block wall,plaster or plasterboard finish on both sides (seeDiagram 5-4)

• for plaster finish, minimum mass per unitarea, including finish 90 kg/m2

• for plasterboard finish, minimum massper unit area, including finish 75 kg/m2


• internal wall type D should only be usedwith the separating walls described inthis Approved Document where there isno minimum mass requirement on theinternal masonry walls. See guidance inSection 2.

• internal wall type D should not be usedas a load-bearing wall or be rigidlyconnected to the separating floorsdescribed in this Approved Document.See guidance in Section 3.


Diagram 5-1: Internal wall type A

PLAN

Diagram 5-2: Internal wall type B

PLAN

Diagram 5-3: Internal wall type C

SECTION


E

5.21 Internal floor type A: Concrete planks(see Diagram 5-5)

• minimum mass per unit area 180 kg/m2

• regulating screed optional

• ceiling finish optional

Note: Insulation against impact sounds can beimproved by adding a soft covering (e.g. carpet).

5.22 Internal floor type B: Concrete beamswith infilling blocks, bonded screed and ceiling(see Diagram 5-6)

• minimum mass per unit area of beamsand blocks 220 kg/m2

• bonded screed required. Sand cementscreeds should have a minimumthickness of 40mm. For proprietarybonded screed products, seekmanufacturers advice on the appropriatethickness

• ceiling finish required. Use ceilingtreatment C or better from Section 3.


5.23 Internal floor type C: Timber or metaljoist, with wood based board and plasterboardceiling, and absorbent material (see Diagram 5-7)

• floor of timber or wood based board,minimum mass per unit area 15 kg/m2

• ceiling treatment of single layer ofplasterboard, minimum mass per unitarea 10 kg/m2, fixed using any normalfixing method

• an absorbent layer of mineral wool(minimum thickness 100 mm, minimumdensity 10 kg/m3) laid in the cavity


Note: Electrical cables give off heat when inuse and special precautions may be requiredwhen they are covered by thermally insulatingmaterials. See BRE BR 262, Thermal Insulation:avoiding risks, section 2.3.


Diagram 5-4: Internal wall type D

SECTION

Diagram 5-5: Internal floor type A

SECTION

Diagram 5-6: Internal floor type B

SECTION

Diagram 5-7: Internal floor type C

SECTION


E

Introduction6.1 Rooms for residential purposes aredefined in Regulation 2 of the BuildingRegulations 2000 (as amended). This definitionis reproduced after the Requirements in thisApproved Document.

6.2 This Section gives examples of wall andfloor types, which, if built correctly, shouldmeet the performance standards set out inSection 0: Performance - Table 1b.


Separating walls in new buildingscontaining rooms for residentialpurposes6.4 Of the separating walls described inSection 2 the following types are most suitablefor use in new buildings containing rooms forresidential purposes:

Wall type 1. Solid masonry

• Wall type 1.1, Dense aggregate concreteblock, plaster on both room faces

• Wall type 1.2, Dense aggregate concretein-situ, plaster on both room faces

• Wall type 1.3, Brick, plaster on both roomfaces

Note: Plasterboard may be used as analternative wall finish, provided a sheet ofminimum mass per unit area 10 kg/m2 is usedon each room face.

Wall type 3. Masonry between independentpanels

• Wall type 3.1, Solid masonry core (denseaggregate concrete block), independentpanels on both room faces

• Wall type 3.2, Solid masonry core(lightweight concrete block), independentpanels on both room faces

Note: Wall types 2 and 4 can be used providedthat care is taken to maintain isolation betweenthe leaves. Specialist advice may be needed.

Corridor walls and doors6.5 Separating walls described in 6.4 shouldbe used between rooms for residentialpurposes and corridors in order to controlflanking transmission and to provide therequired sound insulation between the dwellingand the corridor. However, it is likely that the

sound insulation will be reduced by thepresence of a door.

6.6 Ensure any door has good perimetersealing (including the threshold where practical)and a minimum mass per unit area of 25 kg/m2.Alternatively, use a doorset with a minimumsound reduction index of 29dB Rw (measured inthe laboratory according to BS EN ISO 140-3:1995 and rated according to BS EN ISO 717-1:1997). The door should also satisfy theRequirements of Building Regulation Part B -Fire safety.

6.7 Noisy parts of the building (e.g. functionrooms or bars), should preferably have a lobby,double door or high performance doorset tocontain the noise. Where this is not possible,nearby rooms for residential purposes shouldhave similar protection. However, do ensurethat there are doors that are suitable fordisabled access, see Building Regulation PartM - Access and facilities for disabled people.

Separating floors in new buildingscontaining rooms for residentialpurposes6.8 Of the separating floors described inSection 3 the following types are most suitablefor use in new buildings containing rooms forresidential purposes:

Floor type 1. Concrete base with soft covering

• Floor type 1.1C Solid concrete slab (castin-situ or with permanent shuttering), softfloor covering, ceiling treatment C

• Floor type 1.2B Concrete planks (solid orhollow), soft floor covering, ceilingtreatment B

Note: Floor types 2 and 3 can be usedprovided that floating floors and ceilings arenot continuous between rooms for residentialpurposes. Specialist advice may be needed.

Rooms for residential purposesresulting from a material changeof use6.9 It may be that an existing wall, floor orstair in a building that is to undergo a materialchange of use will achieve the performancestandards set out in Section 0: Performance -Table 1b without the need for remedial work.This would be the case if the construction wassimilar (including flanking constructions) to oneof the constructions in paragraphs 6.4 and 6.8(e.g. for solid walls and floors the massrequirement should be within 15% of the massper unit area of a construction listed in therelevant section).

Section 6: Rooms for residential purposesROOMS FOR RESIDENTIAL PURPOSES


E6.10 For situations where it cannot be shownthat the existing construction will achieve theperformance standards set out in Section 0:Performance - Table 1b, Section 4 describeswall, floor and stair treatments to improve thelevel of sound insulation in dwellings formedby material change of use. These treatmentsmay be used in buildings containing roomsfor residential purposes. Specialist advicemay be needed.

Junction details 6.11 In order for the construction to be fullyeffective, care should be taken to detailcorrectly the junctions between the separatingwall and other elements, such as floors, roofs,external walls and internal walls.

6.12 In the case of new buildings containingrooms for residential purposes, refer to theguidance in Sections 2 and 3 which describesthe junction and flanking details for each of thenew build separating wall and floor types.

6.13 When rooms for residential purposes areformed by material change of use, refer to thenotes and diagrams in Section 4 that describethe junction and flanking details for the walland floor treatments.

6.14 In the case of the junction between asolid masonry separating wall type 1 and theceiling void and roof space, the solid wall neednot be continuous to the underside of thestructural floor or roof provided that:

(a) there is a ceiling consisting of two ormore layers of plasterboard, of minimum totalmass per unit area 20 kg/m2,

(b) there is a layer of mineral wool (minimumthickness 200 mm, minimum density 10 kg/m3)in the roof void,

(c) the ceiling is not perforated.

The ceiling joists and plasterboard sheetsshould not be continuous between rooms forresidential purposes. See Diagram 6-1.

6.15 This ceiling void and roof space detailcan only be used where the Requirements ofBuilding Regulation Part B - Fire safety canalso be satisfied. The Requirements of BuildingRegulation Part L - Conservation of fuel andpower should also be satisfied.

Room layout and building servicesdesign considerations 6.16 Internal noise levels are affected by roomlayout, building services and sound insulation.

6.17 The layout of rooms should beconsidered at the design stage to avoid placingnoise sensitive rooms next to rooms in whichnoise is generated.

6.18 Additional guidance is provided in BS 8233:1999 Sound Insulation and NoiseReduction for Buildings - Code of Practice andSound Control for Homes. See Annex D:References.

ROOMS FOR RESIDENTIAL PURPOSES

mineral wool

ceiling notcontinuousbetween rooms,joints sealedwith tape orflexible sealant

Diagram 6-1: Ceiling void and roof space(only applicable to roomsfor residential purposes)

SECTION


E

Introduction7.1 This Section describes how to determinethe amount of additional absorption to be usedin corridors, hallways, stairwells and entrancehalls that give access to flats and rooms forresidential purposes.

7.2 For the purposes of this Section, acorridor or hallway is a space for which theratio of the longest to the shortest floordimension is greater than three.

7.3 For the purposes of this Section, anentrance hall is a space for which the ratio ofthe longest to the shortest floor dimension isthree or less.

7.4 When an entrance hall, corridor, hallwayor stairwell opens directly into another of thesespaces, the guidance should be followed foreach space individually.

7.5 The choice of absorptive material shouldmeet the Requirements of Building RegulationPart B - Fire safety.

7.6 Two methods are described to satisfyRequirement E3, Method A and Method B.

7.7 Method A: Cover a specified area with anabsorber of an appropriate class that has beenrated according to BS EN ISO 11654:1997Acoustics – Sound absorbers for use inbuildings – Rating of sound absorption.

7.8 Method B: Determine the minimumamount of absorptive material using acalculation procedure in octave bands.Method B is intended only for corridors,hallways and entrance halls as it is not wellsuited to stairwells.

7.9 Where additional guidance is required,specialist advice should be sought at anearly stage.

Method A7.10 For entrance halls, corridors or hallways,cover an area equal to or greater than the floorarea, with a Class C absorber or better. It willnormally be convenient to cover the ceilingarea with the additional absorption.

7.11 For stairwells or a stair enclosure,calculate the combined area of the stair treads,the upper surface of the intermediate landings,the upper surface of the landings (excludingground floor) and the ceiling area on the topfloor. Either, cover at least an area equal to thiscalculated area with a Class D absorber, orcover an area equal to at least 50 % of this

calculated area with a Class C absorber orbetter. The absorptive material should beequally distributed between all floor levels. Itwill normally be convenient to cover theunderside of intermediate landings, theunderside of the other landings, and the ceilingarea on the top floor.

7.12 Method A can generally be satisfied bythe use of proprietary acoustic ceilings.However, the absorptive material can be appliedto any surface that faces into the space.

Method B

7.13 In comparison with Method A, Method Btakes account of the existing absorptionprovided by all surfaces. In some cases,Method B should allow greater flexibility inmeeting Requirement E3 and require lessadditional absorption than Method A.

7.14 For an absorptive material of surfacearea, S in m2, and sound absorption coefficient,α , the absorption area A is equal to the productof S and α .

7.15 The total absorption area, AT, in squaremetres is defined as the hypothetical area of atotally absorbing surface, which if it were theonly absorbing element in the space would givethe same reverberation time as the spaceunder consideration.

7.16 For n surfaces in a space, the totalabsorption area, AT, can be found using thefollowing equation.

7.17 For entrance halls, provide a minimum of0.20 m2 total absorption area per cubic metreof the volume. The additional absorptivematerial should be distributed over theavailable surfaces.

7.18 For corridors or hallways, provide aminimum of 0.25 m2 total absorption area percubic metre of the volume. The additionalabsorptive material should be distributed overone or more of the surfaces.

7.19 Absorption areas should be calculated foreach octave band. Requirement E3 will besatisfied when the appropriate amount ofabsorption area is provided for each octaveband between 250 Hz and 4000 Hz inclusively.

AT = α

1S

1 + α

2S

2 +...+α

nS

n

Section 7: Reverberation in the commoninternal parts of buildings containing flatsor rooms for residential purposes

REVERBERATION (FLATS OR ROOMS FOR RESIDENTIAL PURPOSES)


E7.20 Absorption coefficient data (to two decimalplaces) should be taken from the following:

• For specific products, use laboratorymeasurements of absorption coefficientdata determined using BS EN 20354:1993Acoustics – Measurement of soundabsorption in a reverberation room. Themeasured third octave band data shouldbe converted to practical soundabsorption coefficient data, �p in octavebands, according to BS EN ISO11654:1997 Acoustics – Sound absorbersfor use in buildings – Rating of soundabsorption.

• For generic materials, use Table 7.1. Thiscontains typical absorption coefficientdata for common materials used inbuildings. These data may besupplemented by published octave banddata for other generic materials.

7.21 In Method B, each calculation step is tobe rounded to two decimal places.

Report format7.22 Evidence that Requirement E3 has beensatisfied should be presented, for example on adrawing or in a report, which should include:

(1) A description of the enclosed space(entrance hall, corridor, stairwell etc.)

(2) The approach used to satisfyRequirement E3, Method A or B.

• With Method A, state the absorberclass and the area to be covered.

• With Method B, state the totalabsorption area of additionalabsorptive material used to satisfythe requirement.

(3) Plans indicating the assignment of theabsorptive material in the enclosed space.

Worked example7.23 Example: Entrance hall

The entrance hall has dimensions 3.0 m (width)x 4.0 m (length) x 2.5 m (height). The concretefloor is covered with carpet, the walls arepainted concrete blocks and there are fourtimber doors (1.0 m x 2.4 m).

To satisfy Requirement E3, either use:

• Method A: Cover at least 3.0 x 4.0 = 12 m2

with a Class C absorber or better, or

• Method B: Provide a minimum of 0.2 m2

absorption area per cubic metre of thevolume.

7.24 Method B is described in steps 1 to 8 inTable 7.2. In this example; the designerconsiders that covering the entire ceiling is aconvenient way to provide the additionalabsorption. The aim of the calculation is todetermine the absorption coefficient, �ceiling,needed for the entire ceiling.

7.25 In this example, the absorptioncoefficients from Method B indicate that aClass D absorber could be used to cover theceiling. This can be compared against theslightly higher absorption requirement ofMethod A, which would have used a Class Cabsorber or better to cover the ceiling.

REVERBERATION (FLATS OR ROOMS FOR RESIDENTIAL PURPOSES)

Table 7.1: Absorption coefficient data forcommon materials in buildings

Material Sound absorption coefficient, αin octave frequency bands (Hz)

250 500 1000 2000 4000

Fair-faced concrete 0.01 0.01 0.02 0.02 0.03or plasteredmasonry

Fair-faced brick 0.02 0.03 0.04 0.05 0.07

Painted concrete 0.05 0.06 0.07 0.09 0.08block

Windows, 0.08 0.05 0.04 0.03 0.02glass façade

Doors (timber) 0.10 0.08 0.08 0.08 0.08

Glazed tile/marble 0.01 0.01 0.01 0.02 0.02

Hard floor coverings 0.03 0.04 0.05 0.05 0.06(e.g. lino, parquet)on concrete floor

Soft floor coverings 0.03 0.06 0.15 0.30 0.40(e.g. carpet) onconcrete floor

Suspended plaster 0.15 0.10 0.05 0.05 0.05or plasterboardceiling (with largeairspace behind)


EREVERBERATION (FLATS OR ROOMS FOR RESIDENTIAL PURPOSES)

Step 1 Calculate the surface area related to each absorptive material (i.e. for the floor, walls, doors and ceiling).

Surface Surface finish Area (m2)

Floor Carpet on concrete base 12.00Doors Timber 9.60Walls (excluding door area) Concrete block, painted 25.40Ceiling To be determined from this calculation 12.00

Step 2 Obtain values of absorption coefficients for the carpet, painted concrete block walls and the timber doors. In this case, thevalues are taken from Table 7.1.

Absorption coefficient (�) in octave frequency bands

Surface Area (m2) 250 Hz 500 Hz 1000 Hz 2000 Hz 4000 Hz

Floor 12.00 0.03 0.06 0.15 0.30 0.4Doors 9.60 0.10 0.08 0.08 0.08 0.08Walls 25.40 0.05 0.06 0.07 0.09 0.08Ceiling 12.00 To be determined from this calculation

Step 3 Calculate the absorption area (m2) related to each absorptive surface (i.e. for the floor, walls and doors) in octave frequencybands (Absorption area = surface area x absorption coefficient).

Absorption area (m2)

Surface 250 Hz 500 Hz 1000 Hz 2000 Hz 4000 Hz

Floor 0.36 0.72 1.80 3.60 4.80(12.00 x 0.03)

Doors 0.96 0.77 0.77 0.77 0.77(9.60 x 0.10)

Walls 1.27 1.52 1.78 2.29 2.03(25.40 x 0.05)

Step 4 Calculate the sum of the absorption areas (m2) obtained in step 3

250 Hz 500 Hz 1000 Hz 2000 Hz 4000 Hz

Total absorption area (m2) 2.59 3.01 4.35 6.66 7.60(0.36 + 0.96

+ 1.27)

Step 5 Calculate the total absorption area (A T) required for the entrance hall. The volume is 30 m3 and therefore 0.2 x 30.0 = 6.0 m2

of absorption area is required.

AT (m2) 6.00

Step 6 Calculate additional absorption area (A) to be provided by ceiling (m2). If any values of minimum absorption area are negative,e.g. see 2000 Hz and 4000 Hz, then there is sufficient absorption from the other surfaces to meet the requirement without anyadditional absorption in this octave band. (Additional absorption = A T – total absorption area (from Step 5))

250 Hz 500 Hz 1000 Hz 2000 Hz 4000 Hz

Additional absorption area (m2) 3.41 2.99 1.65 -0.66 -1.60(6.00 – 2.59) N.B. negative values indicate that no

additional absorption is necessary.

Step 7 Calculate required absorption coefficient (α) to be provided by ceiling (Required absorption coefficient α = Additionalabsorption area / area of ceiling)

250 Hz 500 Hz 1000 Hz 2000 Hz 4000 Hz

Required absorption coefficient, α 0.28 0.25 0.14 Any value Any value(3.41 ÷ 12.0)

Step 8 Identify a ceiling product from manufacturer’s laboratory measurement data that provides absorption coefficients that exceedthe values calculated in step 7.

Table 7.2: Example calculation for an entrance hall (Method B)


E

8.1 In the Secretary of State’s view thenormal way of satisfying Requirement E4 willbe to meet the values for sound insulation,reverberation time and internal ambient noisewhich are given in Section 1 of BuildingBulletin 93 ‘The Acoustic Design of Schools’,produced by DfES and published by theStationery Office (ISBN: 0 11 271105 7) (to bepublished during 2003).

Section 8: Acoustic conditions in schoolsACOUSTIC CONDITIONS IN SCHOOLS

A1 Wall massA1.1 Where a mass is specified it is expressedas mass per unit area in kilograms per squaremetre (kg/m2).

A1.2 The mass may be obtained from themanufacturer or it may be calculated by themethod given in this annex. To calculate themass per unit area of a masonry leaf use theformula below. This formula is not exact but issufficient for this purpose.

A2 Formula for calculation of wallleaf mass per unit area. A2.1 Mass per unit area of a brick/block leaf

= mass of co-ordinating area / co-ordinatingarea

where

MB is brick/block mass (kg) at appropriatemoisture content

ρm is density of mortar (kg/m3) at appropriatemoisture content

T is the brick/block thickness withoutsurface finish (m)

d is mortar thickness (m)

L is co-ordinating length (m)

H is co-ordinating height (m)

V is volume of any frog/void filled withmortar (m3)

Note: This formula provides the mass per unitarea of the block/brick construction withoutsurface finish.

Note: See Diagram A.1 for block and mortardimensions.

A2.2 When calculating the mass per unit areafor bricks and blocks use the density at theappropriate moisture content from Table 3.2,CIBSE Guide A (1999).

A2.3 For cavity walls the mass per unit area ofeach leaf is calculated and added together.

A2.4 Where surface finishes are used the massper unit area of the finish is added to the massper unit area of the wall.

A3 Simplified equationsA3.1 Two examples are given (see Table A.1and A.2) using the equation in A2.1. For eachof these examples a simplified equation isobtained for that type of construction.

MB + ρ

m(Td (L + H - d) +V)

= kg/m2

LH


E

Annex A: Method for calculating mass perunit area

METHOD FOR CALCULATING MASS PER UNIT AREA

co=ordinating area(shaded)

L

H

d

d

T

Diagram A-1: Block and mortardimensions

Example of single leaf wall, blocks laid flat

• d = 0.010 m

• T = 0.215 m

• L = 0.450 m

• H = 0.110 m

• V = 0 m3

• ρm = 1800 kg/m3

• No surface finish

Mass per unit area = 20.2MB + 43.0 kg/m2

Substituting for MB in this formula gives the following values:

Block mass, MB (kg) Mass per unit area (kg/m2)

6 164

8 205

10 245

12 285

14 326

16 366

18 407

Table A.1 Blocks laid flat

A4 Mass per unit area of surfacefinishesA4.1 The mass per unit area of surface finishesshould be obtained from manufacturer’s data.

A5 Mass per unit area of floorsA5.1 The mass of a solid and homogeneousfloor (without hollows, beams or ribs) can becalculated from:

MF = ρc x T

where,

MF is mass per unit area of floor (kg/m2)

ρc is density of concrete (kg/m3)

T is thickness of floor (m)

A5.2 The mass of a beam and block floor canbe calculated from:

MF = (Mbeam,1m + Mblock,1m) / LB

where

MF is mass per unit area of floor (kg/m2)

Mbeam,1m is the mass of a 1 m length of beam (kg)

Mblock,1m is the mass of a 1 m length of blocks (kg)

LB is the distance between the beam centrelines, i.e. the repetition interval (m)

Note: See Diagram A.2 for beam and blockfloor dimensions.

A5.3 For other floor types (including floors withvariable thickness), seek advice from themanufacturer on mass per unit area andperformance.


E METHOD FOR CALCULATING MASS PER UNIT AREA

Example of single leaf wall, blocks laid on edge

• d = 0.010 m

• T = 0.100 m

• L = 0.450 m

• H = 0.225 m

• V = 0 m3

• ρm = 1800 kg/m3

• No surface finish

Single leaf wall:Mass per unit area = 9.9MB + 11.8 kg/m2

Cavity wall:Mass per unit area = 19.8MB + 23.6 kg/m2

Substituting for MB in this formula gives the following values:

Block mass, MB (kg) Mass per unit area (kg/m2)

Single leaf Cavity

6 71 1428 91 18210 111 22212 131 26114 150 30116 170 34018 190 380

Table A.2: Blocks laid on edge

1m

LB

Diagram A-2: Beam and block floordimensions

SECTION

PLAN

B1 IntroductionB1.1 Section B.2 of this Annex describes thesound insulation testing procedure approved bythe Secretary of State for the purposes ofRegulation 20A (2)(a) of the BuildingRegulations and Regulation 12A (2)(a) of theApproved Inspectors Regulations. The approvedprocedure is that set out in Section B.2 and theStandards referred to in that Section.

B1.2 Section B.3 of this Annex providesguidance on laboratory testing in connectionwith achieving compliance with Requirement E2in Schedule 1 to the Building Regulations, andin connection with evaluation of components tobe used in constructions subject toRequirement E1.

B1.3 Section B.4 of this Annex gives guidanceon test reports.

B1.4 The person carrying out the building workshould arrange for sound insulation testing tobe carried out by a test body with appropriatethird party accreditation. Test bodiesconducting testing should preferably haveUKAS accreditation (or a European equivalent)for field measurements. The measurementinstrumentation used should have a valid,traceable certificate of calibration, and shouldhave been tested within the past two years.

B2 Field measurement of soundinsulation of separating walls andfloors for the purposes ofRegulation 20A and Regulation 12AIntroduction

B2.1 Sound insulation testing for the purposesof Regulation 20A of the Building Regulationsand Regulation 12A of the Approved InspectorsRegulations 2000, must be done in accordancewith: BS EN ISO 140-4:1998; BS EN ISO 140-7:1998; BS EN ISO 717-1:1997; BS EN ISO717-2:1997; BS EN 20354:1993. Whencalculating sound insulation test results, norounding should occur in any calculation untilrequired by the relevant Standards, the BS ENISO 140 series and the BS EN ISO 717 series.

Airborne sound insulation of a separatingwall or floor

B2.2 The airborne sound insulation of aseparating wall or floor should be measured inaccordance with BS EN ISO 140-4:1998. Allmeasurements and calculations should becarried out using one-third-octave frequencybands. Performance should be rated in termsof the weighted standardized level difference,

DnT,w, and spectrum adaptation term, Ctr, inaccordance with BS EN ISO 717-1:1997.

Measurements using a single sound source

B2.3 For each source position, the averagesound pressure level in the source andreceiving rooms is measured in one-third-octave bands using either fixed microphonepositions (and averaging these values on anenergy basis), or using a moving microphone.

B2.4 For the source room measurements, thedifference between the average sound pressurelevels in adjacent one-third-octave bandsshould be no more than 6 dB. If this conditionis not met, the source spectrum should beadjusted and the source room measurementrepeated. If the condition is met, the averagesound pressure level in the receiving room, andhence a level difference, should be determined.

B2.5 It is essential that all measurements madein the source and receiving rooms to determinea level difference should be made withoutmoving the sound source or changing the outputlevel of the sound source, once its spectrum hasbeen correctly adjusted (where necessary).

B2.6 The sound source should now be movedto the next position in the source room and theabove procedure repeated to determineanother level difference. At least two positionsshould be used for the source. The leveldifferences obtained from each source positionshould be arithmetically averaged to determinethe level difference, D as defined in BS EN ISO140-4:1998.

Measurements using multiple sound sourcesoperating simultaneously

B2.7 For multiple sound sources operatingsimultaneously, the average sound pressurelevel in the source and receiving rooms ismeasured in one-third-octave bands usingeither fixed microphone positions (andaveraging these values on an energy basis), orusing a moving microphone.

B2.8 For the source room measurements, thedifference between the average sound pressurelevels in adjacent one-third-octave bandsshould be no more than 6 dB. If this conditionis not met, the source spectrum should beadjusted and the source room measurementrepeated. If the condition is met, determine theaverage level in the receiving room, and hencethe level difference, D as defined in BS EN ISO140-4:1998.


E

Annex B: Procedures for sound insulationtesting

PROCEDURES FOR SOUND INSULATION TESTING

Impact sound transmission of a separatingfloor

B2.9 The impact sound transmission of aseparating floor should be measured inaccordance with BS EN ISO 140-7:1998. Allmeasurements and calculations should becarried out using one-third-octave frequencybands. Performance should be rated in termsof the weighted standardized impact soundpressure level, L’nT,w in accordance withBS EN ISO 717-2:1997.

Measurement of reverberation time

B2.10 BS EN ISO 140-4:1998 andBS EN ISO 140-7:1998 refer to theISO 354 (BS EN 20354:1993) method formeasuring reverberation time. However for theapproved procedure, the guidance inBS EN ISO 140-7:1998 relating to the source andmicrophone positions, and the number of decaymeasurements required, should be followed.

Room requirements

B2.11 Section 1 gives guidance on the roomtypes that should be used for testing. Theserooms should have volumes of at least 25 m3. Ifthis is not possible then the volumes of therooms used for testing should be reported.

Tests between rooms

B2.12 Tests should be conducted in completedbut unfurnished rooms or available spaces inthe case of properties sold before fitting out;see Section 1.

B2.13 Impact sound insulation tests should beconducted on a floor without a soft covering(e.g. carpet, foam backed vinyl etc) except inthe case of (a) separating floor type 1, asdescribed in this Approved Document, or (b) aconcrete structural floor base which has a softcovering as an integral part of the floor.

B2.14 If a soft covering has been installed onany other type of floor, it should be taken up. Ifthat is not possible, at least half of the floorshould be exposed and the tapping machineshould be placed only on the exposed part ofthe floor.

B2.15 When measuring airborne soundinsulation between a pair of rooms of unequalvolume, the sound source should be in thelarger room.

B2.16 Doors and windows should be closed.

B2.17 Kitchen units, cupboards etc. on all wallsshould have their doors open and be unfilled.

Measurement precision

B2.18 Sound pressure levels should bemeasured to 0.1 dB precision.

B2.19 Reverberation times should bemeasured to 0.01 s precision.

Measurements using a moving microphone

B2.20 At least two positions should be used.

B2.21 For measurements of reverberation time,discrete positions should be used rather than amoving microphone.

B3 Laboratory measurementsIntroduction

B3.1 Pre-completion testing for the purposesof Regulation 20A and Regulation 12A involvesfield testing on separating walls and floors (seeSection 1 and Annex B: B2). However, there areapplications for laboratory tests to determinethe performance of: floor coverings; floatingfloors; wall ties; resilient layers; internal wallsand floors; and flanking laboratory tests toindicate the performance of novel constructions.

B3.2 When calculating sound insulation testresults, no rounding should occur in anycalculation until required by the relevantStandards, i.e. the BS EN ISO 140 series andthe BS EN ISO 717 series.

Tests on floor coverings and floating floors

B3.3 Floor coverings and floating floorsshould be tested in accordance with BS EN ISO 140-8:1998 and rated inaccordance with BS EN ISO 717-2:1997. Thetest floor should have a thickness of 140 mm.

B3.4 It should be noted that text has beenomitted from BS EN ISO 140-8:1998. For thepurposes of this Approved Document, section6.2.1 of BS EN ISO 140-8:1998 should bedisregarded, and section 5.3.3 of BS EN ISO140-7:1998, respectively, referred to instead.

B3.5 BS EN ISO 140-8:1998 refers to theISO 354 (BS EN 20354:1993) method formeasuring reverberation time, but the guidance inBS EN ISO 140-8:1998 relating to the source andmicrophone positions, and the number of decaymeasurements required, should be followed.

B3.6 When assessing category II test specimens(as defined in BS EN ISO 140-8:1998) for use withseparating floor type 2, the performance value(�Lw) should be achieved when the floating floor isboth loaded and unloaded. The loadedmeasurements should use a uniformly distributedload of 20-25 kg/m2 with at least one weight persquare metre of the flooring area, as described inBS EN ISO 140-8:1998.

Dynamic stiffness of resilient layers

B3.7 Dynamic stiffness of resilient layersshould be measured in accordance withBS EN 29052-1:1992. The test method usingsinusoidal signals should be used. No pre-compression should be applied to the testspecimens before the measurements.


E PROCEDURES FOR SOUND INSULATION TESTING

Dynamic stiffness of wall ties

B3.8 Dynamic stiffness of wall ties should bemeasured in accordance with BRE InformationPaper IP 3/01.

Airborne sound insulation of internal walland floor elements

B3.9 The airborne sound insulation of internalwall or floor elements in a laboratory should bemeasured in accordance withBS EN ISO 140-3:1995, and the performancerated in accordance with BS EN ISO 717-1:1997to determine the weighted sound reductionindex, Rw.

Measurements in a flanking laboratory

B3.10 Tests of sound transmission in a flankinglaboratory include both direct and flankingpaths, and are a useful means of assessing thelikely field performance of novel constructions.

B3.11 It is not possible to demonstratecompliance with Requirement E1 using testresults from a flanking laboratory.

Flanking laboratory: Design

B3.12 Construction details of a suitablelaboratory can be obtained from the AcousticsCentre, BRE, Garston, Watford WD25 9XX.

Note: A CEN standard for the laboratorymeasurement of flanking transmission betweenadjoining rooms is currently underdevelopment.

Flanking laboratory: Indicative airbornesound insulation values

B3.13 When a test construction has airbornesound insulation of at least 49 dB DnT,w + Ctr

when measured in a flanking laboratory usingthe procedure given in Annex B: B2, this canbe taken as indicative that the sameconstruction (i.e. identical in all significantdetails) may achieve at least 45 dB DnT,w + Ctr

when built in the field. See paragraph B3.11.

Flanking laboratory: Indicative impact soundinsulation values

B3.14 When a test construction has impactsound insulation no more than 58 dB L’nT,w

when measured in a flanking laboratory usingthe procedure given in Annex B: B2, this canbe taken as indicative that the sameconstruction (i.e. identical in all significantdetails) may achieve no more than 62 dB L’nT,w

when built in the field. See paragraph B3.11.

B4 Information to be included intest reportsField test reports

B4.1 Paragraph 1.41 of this ApprovedDocument sets out the manner of recording theresults of testing done for the purposes of

Regulation 20A or Regulation 12A, approved bythe Secretary of State under those Regulations.

Although not required, it may be useful to havea description of the building including:

1. sketches showing the layout anddimensions of rooms tested;

2. description of separating walls, externalwalls, separating floors, and internalwalls and floors including details ofmaterials used for their construction andfinishes;

3. mass per unit area in kg/m2 ofseparating walls, external walls,separating floors, and internal walls andfloors;

4. dimensions of any step and/or staggerbetween rooms tested;

5. dimensions and position of any windowsor doors in external walls.

Laboratory test reports for internal walls andfloors

B4.2 Test reports should include the followinginformation.

1. Organisation conducting test, including:

(a) name and address;

(b) third party accreditation number(e.g. UKAS or European equivalent);

(c) Name(s) of person(s) in charge of test.

2. Name(s) of client(s).

3. Date of test.

4. Brief details of test, including:

(a) equipment;

(b) test procedures.

5. Full details of the construction undertest and the mounting conditions.

6. Results of test shown in tabular andgraphical form for third octave bandsaccording to the relevant part of theBS EN ISO 140 series and BS EN ISO 717series, including:

(a) single-number quantity and thespectrum adaptation terms;

(b) data from which the single-numberquantity is calculated.


EPROCEDURES FOR SOUND INSULATION TESTING

The definitions given below are for thepurposes of this document only, and are notintended to be rigorous. Fuller definitions ofthe various acoustical terms are to be foundin the relevant British Standards listed inAnnex D.

AbsorptionConversion of sound energy to heat, often bythe use of a porous material.

Absorption coefficientA quantity characterizing the effectiveness of asound absorbing surface. The proportion ofsound energy absorbed is given as a numberbetween zero (for a fully reflective surface) andone (for a fully absorptive surface). Note thatsound absorption coefficients determined fromlaboratory measurements may have valuesslightly larger than one. See BS EN 20354:1993.

Absorptive materialMaterial that absorbs sound energy.

Airborne soundSound propagating through the air.

Airborne sound insulationSound insulation that reduces transmission ofairborne sound between buildings or parts ofbuildings.

Air pathA direct or indirect air passage from one sideof a structure to the other.

CaulkingProcess of sealing joints.

Cavity stopA proprietary product or material such as mineralwool used to close the gap in a cavity wall.

Ctr

The correction to a sound insulation quantity(such as DnT,w) to take account of a specificsound spectra. See BS EN ISO 717-1:1997.

dB (See decibel)

Decibel (dB)The unit used for many acoustic quantities toindicate the level with respect to a reference level.

DensityMass per unit volume, expressed in kilogramsper cubic metre (kg/m3).

Direct transmissionThe process in which sound that is incident onone side of a building element is radiated bythe other side.

DnT

The difference in sound level between a pair ofrooms, in a stated frequency band, correctedfor the reverberation time. SeeBS EN ISO 140-4:1998.

DnT,w

A single-number quantity which characterizesthe airborne sound insulation between rooms.See BS EN ISO 717-1:1997.

DnT,w + Ctr

A single-number quantity which characterizesthe airborne sound insulation between roomsusing noise spectrum no. 2 as defined inBS EN ISO 717-1:1997. SeeBS EN ISO 717-1:1997.

Dynamic stiffnessA parameter used to describe the ability of aresilient material or wall tie to transmit vibration.Specimens with high dynamic stiffness(dynamically ‘stiff’) transmit more vibration thanspecimens with low dynamic stiffness(dynamically ‘soft’). See BS EN 29052-1:1992for resilient materials. See BRE InformationPaper IP 3/01 for wall ties.

Flanking elementAny building element that contributes to soundtransmission between rooms in a building thatis not a separating floor or separating wall.

Flanking transmissionSound transmitted between rooms via flankingelements instead of directly through separatingelements or along any path other than thedirect path.

Floating floorA floating floor consists of a floating layer andresilient layer (see also resilient layer andfloating layer).

Floating layer A surface layer that rests on a resilient layerand is therefore isolated from the base floor andthe surrounding walls (see also resilient layer).

Framed wallA partition consisting of board or boardsconnected to both sides of a wood or metal frame.

FrequencyThe number of pressure variations (or cycles)per second that gives a sound its distinctivetone. The unit of frequency is the Hertz (Hz).

Frequency bandA continuous range of frequencies betweenstated upper and lower limits, (see also octaveband and one-third-octave band).

Hertz (Hz)The unit of the frequency of a sound (formerlycalled cycles per second).

Annex C: Glossary


E GLOSSARY

Impact soundSound resulting from direct impact on abuilding element.

Impact sound insulationSound insulation which reduces impact soundtransmission from direct impacts such asfootsteps on a building element.

Independent ceilingA ceiling which is fixed independently of aseparating floor or an internal floor (seeseparating floor and internal floor).

Internal floorAny floor that is not a separating floor (seeseparating floor).

Intermediate landingA landing between two floors (see also landing).

Internal wallAny wall that does not have a separating function.

IsolationThe absence of rigid connections between twoor more parts of a structure.

LandingA platform or part of floor structure at the endof a flight of stairs or ramp.

L’nT

The impact sound pressure level in a statedfrequency band, corrected for the reverberationtime. See BS EN ISO 140-7:1998.

L’nT,w

A single-number quantity used to characterizethe impact sound insulation of floors. SeeBS EN ISO 717-2:1997.

Mass per unit area Mass per unit area is expressed in terms ofkilograms per square metre (kg/m2).

NoiseNoise is unwanted sound.

Octave bandA frequency band in which the upper limit of theband is twice the frequency of the lower limit.

One-third-octave bandA frequency band in which the upper limit of theband is 21/3 times the frequency of the lower limit.

Rw

A single-number quantity which characterizesthe airborne sound insulation of a material orbuilding element in the laboratory. SeeBS EN ISO 717-1:1997.

Resilient layerA layer that isolates a floating layer from abase floor and surrounding walls.

ReverberationThe persistence of sound in a space after asound source has been stopped.

Reverberation timeThe time, in seconds, taken for the sound todecay by 60 dB after a sound source hasbeen stopped.

Separating floorFloor that separates flats or rooms forresidential purposes.

Separating wallWall that separates adjoining dwelling-houses,flats or rooms for residential purposes.

Sound pressure levelA quantity related to the physical intensity ofa sound.

Sound reduction index (R)A quantity, measured in a laboratory, whichcharacterizes the sound insulating properties ofa material or building element in a statedfrequency band. See BS EN ISO 140-3:1995.

SpectrumThe composition of a particular sound in termsof separate frequency bands.

Structure-borne soundSound which is carried via the structure of abuilding.

UKASUnited Kingdom Accreditation Service.

∆Lw

The measured improvement of impact soundinsulation resulting from the installation of afloor covering or floating floor on a test floor ina laboratory. See BS EN ISO 717-2:1997.


EGLOSSARY

D1 StandardsBS Series

BS 1243:1978 Metal ties for cavity wallconstruction.

BS 5628-3:2001 Code of practice for use ofmasonry. Part 3. Materials and components,design and workmanship.

BS 8233:1999 Sound Insulation and NoiseReduction for Buildings – Code of practice.

BS EN Series

BS EN 20354:1993 Acoustics – Measurementof sound absorption in a reverberation room.

BS EN 29052-1:1992 Acoustics – Method for thedetermination of dynamic stiffness. Part 1.Materials used under floating floors in dwellings.

BS EN ISO Series

BS EN ISO 140-3:1995 Acoustics –Measurement of sound insulation in buildingsand of building elements. Part 3. Laboratorymeasurement of airborne sound insulation ofbuilding elements.

BS EN ISO 140-4:1998 Acoustics –Measurement of sound insulation in buildingsand of building elements. Part 4. Fieldmeasurements of airborne sound insulationbetween rooms.

BS EN ISO 140-6:1998 Acoustics – Measurementof sound insulation in buildings and of buildingelements. Part 6. Laboratory measurements ofimpact sound insulation of floors.

BS EN ISO 140-7:1998 Acoustics – Measurementof sound insulation in buildings and of buildingelements. Part 7. Field measurements of impactsound insulation of floors.

BS EN ISO 140-8:1998 Acoustics –Measurement of sound insulation in buildingsand of building elements. Part 8. Laboratorymeasurements of the reduction of transmittedimpact noise by floor coverings on aheavyweight standard floor.

BS EN ISO 717-1:1997 Acoustics – Rating ofsound insulation in buildings and of buildingelements. Part 1. Airborne sound insulation.

BS EN ISO 717-2:1997 Acoustics – Rating ofsound insulation in buildings and of buildingelements. Part 2. Impact sound insulation.

BS EN ISO 11654:1997 Acoustics – Soundabsorbers for use in buildings – Rating ofsound absorption.

D2 GuidanceBuilding Bulletin 93 ‘The Acoustic Design ofSchools’, produced by DfEE. ISBN: 0 11271105 7 (to be published during 2003).

BRE IP 3/01 Dynamic stiffness of wall ties usedin masonry cavity walls: measurementprocedure. CRC Ltd, 2001, ISBN 1 86081 461 1.

BRE IP 4/01 Methods for reducing impact andstructure borne sound in buildings, CRC Ltd,2001, ISBN 1 86081 462 X.

BRE IP 14/02 Dealing with poor soundinsulation between new dwellings, CRC Ltd, 2002, ISBN 1 86081 5490

BRE BR 262 Thermal insulation : avoiding risks,CRC Ltd, 2002, ISBN 86081 515 4.

Sound Control for Homes (BRE report 238,CIRIA report 127 available from CRC Ltd).Note: Some of the information within thisdocument has been superseded.

Construction Products Directive (89/106/EEC).

CIBSE Guide A, Environmental design, 1999,ISBN 0 900953 96 9.

D3 Other legislationConstruction Products Regulations 1991. SI1991 No.1620.

Construction Products (Amendment)Regulations 1994. SI 1994 No.3051.

CE marking Directive (93/68/EEC).

The Gas Safety (Installation and Use)Regulations 1998, SI 1998 No.2451.

The Workplace (Health, Safety and Welfare)Regulations 1992, Approved Code of Practiceand Guidance; The Health and SafetyCommission, L24;HMSO 1992; ISBN 0-11-886333-9.

Annex D: References


E REFERENCES

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