Multinail Hub - Bearing Plate

Multinail Australia

Multinail Hub - Bearing Plate27 May 2020

Due to continual product improvement Multinail Australia Pty Ltd. reserves the right to change the product/s depicted - both in description and specification.This document has to be read in conjunction with Multinail’s Technical Manual.

Bearing Plate

Below is a table showing the maximum bearing capacity of timber.

When these capacities are exceeded, bearing conditions must be improved byeither increasing bearing area and/or timber strength group, or installing abearing enhancer ancillary such as a bearing plate.

Truss Thickness (mm) Timber Strength GroupMaximum Bearing Capacity (kN)

Dead Load - 1.35DL

Softwood

35 SD6 10.9

45 SD6 13.7

70 SD6 20.7

90 SD6 26.3

Hardwood

35 SD4 22.5

45 SD4 28.3

70 SD4 42.7

90 SD4 54.2

Note:

The Strength Group for Seasoned Radiata Pine and MGP is SD6 ; Hardwoodis SD4

Softwood (SD6) - Max. Bearing Stress = 10MPa (1.35DL) with a CapacityFactor (ɸ) of 0.7

Hardwood (SD4) - Max. Bearing Stress = 17MPa (1.35DL) with a CapacityFactor (ɸ) of 0.85

https://www.multinail.net/technical-manual-au/roof-trusses/c1-roof-truss-guidelines/c1-05-01?

Multinail Australia

Multinail Hub - Cranked Rafter27 May 2020

Cranked Rafter

DetailOverall

Roofing Material Rafter span (mm) Member Size Plate Size

1a1b

Sheet 2000 90x35-P10 MN 75x200 MNH 64x200

2 Sheet 2750 120x35-P12 MN 100x125

3 Sheet 3500 140x35-F27 MNH 100x150

4 Tile 2000 120x35-P10 MN 75x200

5 Tile 2750 140x35-F27 MN 100x100

6 Tile 3500 190x35-F27 MN 150x150

Notes:

Rafters at 600 centres

Roof pitch between 15° - 35° (15°- 27.5° for detail 1)

Wind classification – N3

Due to nailplate protrusion limit of 15mm, maximum roof pitch used fordesigning cranked rafter is 20° for detail 1a, and 27.5° for detail 1b.

Please take care when handling this rafter as protruding plates may causeinjury.

Protruding nailplates should be bent over and fixed to the top of the rafter toavoid any injury.

Detail 1a

Figure C1-06-01-01

Detail 1b

Figure C1-06-01-02


Detail 2

Figure C1-06-01-03

Detail 3

Figure C1-06-01-04

Detail 4

Figure C1-06-01-05

Detail 5

Figure C1-06-01-06

Detail 6

Figure C1-06-01-07


Multinail Australia

Multinail Hub - Erection Criteria27 May 2020


Erection CriteriaThe following specification refers only to trusses approved by MULTINAIL towithstand all applied loads for the situation in which they are to be installed.

Trusses to be erected with the spacing such that the centre tocentre distance does not exceed design spacing plus thickness oftruss.Trusses to be erected as per the layout.Trusses to be erected such that at any section the local “Out-Of-Plumb” should not exceed the truss height/50 or 50mm (see FigureC1-01-01-03)Trusses to be erected with overall bow not exceeding the lesser ofSpan/200 and 50mm. The bow in any chord to not exceed memberlength/200 or 50mm. (see Figure C1-01-01-04 & Figure C1-01-01-05)Please refer to the AS 4440 for the Australian Standards fortolerances in erection. Also included in Multinails “The Guide”.

Note: Generally, if bow or tilt is evident to the eye, the truss has probably beenerected outside the tolerances

Figure C1-01-01-01

Figure C1-01-01-02

Figure C1-01-01-03

Figure C1-01-01-04 Figure C1-01-01-05

Ensure Girder Propped

All trusses must be correctly restrained and braced before carrying loads. Where trusses are carrying load and are not fully restrained and braced they may need tobe temporarily propped to help members resist buckling. This commonly occurs with girder trusses during construction. It is recommended to temporarily prop trussesat panel points as shown below.

Figure C1-01-01-06 Figure C1-01-01-07


Multinail Australia

Multinail Hub - Fixing Details for Multiple Laminated Trusses27 May 2020


Fixing Details for Multiple Laminated Trusses

The following details are to ensure an even distribution of forces through equalcomponents of the truss to be manufactured with two or three laminations.

Figure C1-02-01-01

Notes On Laminating Methods:

Each laminate to be manufactured separately with nailplates eitherside of each truss lamination.All members to be in line.The nailing detail refers to maximum 50mm thick laminates only.Refer to Multinail Engineers if additional details are required.Refer to Multinail Engineers for details on four or more trusslaminates.The laminating details are to be carried out with no interference tothe nail plates.Every roof batten must be fixed to every truss laminate with aminimum of 1 effective 2.8mm diameter nail.

https://www.multinail.net/technical-manual-au/roof-trusses/c1-roof-truss-guidelines/laminated-trusses/c1-03-01?

Multinail Australia

Multinail Hub - Girder Brackets - General27 May 2020


Girder Brackets - General

Multinail Girder Brackets are designed for connecting trusses or rafters to thebottom chord of a Girder Truss.

Figure C1-07-01-01

Here below are six types of Multinail truss boots and hangers:

1. Joist Hanger - Low Loading2. Multi Girder Bracket - Medium Loading3. Easy Fix Girder Bracket - Medium Loading4. Split Hanger - Medium Loading5. High Load Easy Fix Girder Bracket - High Loading6. High Load Truss Boots - High Loading


Multinail Australia

Multinail Hub - Internal support offset27 May 2020


Internal support offsetThe maximum offset tolerance of internal support is the depth of the bottom chord (D), from edge of support to edge of web.

Figure C1-09-01-01 Figure C1-09-01-02

Notes: contact Multinail engineering for support offset outside allowable limits


Multinail Australia

Multinail Hub - Laminating Details for Double Trusses27 May 2020


Laminating Details for Double Trusses

Laminating Methods

Top and Bottom Chords

Nail chords together using 3.05Ø mm nails at 300mm centres staggered fromone side or use 1/Green Tip screw at 600mm centres.

Webs

Nail webs together using 3.05Ø mm nails at 450mm centres from one side, butensuring a minimum of two nails to each web or use Green Tip screws at600mm centres.

Note:

For up to 38mm thick laminates use 65mm long nailsFor up to 50mm thick laminates use 75mm long nails

Figure C1-03-02-01

Figure C1-03-02-02


Multinail Australia

Multinail Hub - Laminating Details for Triple Trusses27 May 2020


Laminating Details for Triple Trusses

Laminating Methods

Top and Bottom Chords

Nail as for double truss, and also use 1/M12 bolt at every member junction oruse 2/Black Tip screws at every junction. If bolted brackets are used on thebottom chord at 1200mm centres or less, then these bolts are sufficient forbottom chord.

Webs

Same as for double truss with nails connecting each lamination.

Note:

For 38mm thick laminates use 100mm long Black Tip screws and 65 long nails

Figure C1-03-03-01

Figure C1-03-03-02

Figure C1-03-03-03 Figure C1-03-03-04


Multinail Australia

Multinail Hub - Lifting On Site27 May 2020


Lifting On SiteThe following diagrams show the correct method of lifting and handling trusseson site. Trusses may also be pulled up to the wall top plates using skids placedapproximately 3m apart.

Slings should be located at equal distances from the truss centreline, and beapproximately one-third to one-half truss length apart.

SAFETY NOTE

When lifting, special care must be taken to avoid damage to truss joints. If it isnecessary to handle a truss on its side, precautions must be taken to avoiddamage due to sagging. Trusses must never be lifted by the apex joint only.Spreader bars (with attachment to panel points) must be used where the spanexceeds 9m. For spans over 16m contact the Multinail Engineering Department.

Spans under 9m

Figure C1-02-01-01 Figure C1-02-01-02

Spans 9m to 16m

Figure C1-02-01-03 Figure C1-02-01-04


Multinail Australia

Multinail Hub - Roof Batten Span Table27 May 2020

Roof Batten Span Table

Design Criteria

Roof material Metal Sheeting

Wind velocity N1 + N2

Maximum building width 16.0m

Maximum building height 8.5m (6.0m to eaves)

Notes:

Member continuous over a minimum of three equal spans.Contact Multinail Engineering for more informationTables from AS1684


F5

Maximum spans for battens (General Roof Area)

Spacing

600 900 1200

Size (Actual) Span Overhang Span Overhang Span Overhang

35x70 650 250 500 225 500 200

35x90 850 300 650 250 650 250

45x70 1100 350 850 300 850 275

45x90 1200 425 1100 375 1100 325

MGP10


Spacing

600 900 1200


35x70 800 275 650 250 650 225

35x90 1050 325 800 300 800 275

45x70 1200 400 1050 350 1050 325

45x90 1200 500 1200 425 1200 400

MGP12


Spacing

600 900 1200


35x70 1200 425 1050 375 1050 325

35x90 1200 550 1200 450 1200 400

45x70 1200 600 1200 550 1200 500

45x90 1200 600 1200 600 1200 600

https://www.multinail.net/technical-manual-au/roof-trusses/c1-roof-truss-guidelines/roof-battens-purlins/c1-04-05?

Multinail Australia

Multinail Hub - Roof Batten Splicing Criteria27 May 2020

Roof Batten Splicing Criteria

The following roof batten splicing details are recommended to adequatelyprovide lateral restraint to the roof truss top chords for all metal sheet roofs.

Batten tie down and size to be designed by others

Rules given in AS4440 and “The Guide” must also be followed which include:

Do not splice battens on girder trussesFix each batten to every lamination of every truss with min. 2/nailsAdjacent battens should not be spliced in the same pointNot more than 1 in 3 battens to be spliced on any truss top chord

Design Criteria

Roof material Steel Sheeting

Truss centres 1200mm max.

Batten size 35 x 70 min. 45 x 90 max.

Batten spacing 1200mm max.

Option 1

Figure C1-04-02-01

Option 2

Figure C1-04-02-02

Option 3

Figure C1-04-02-03

Option 4

Figure C1-04-02-04



Option 5

Figure C1-04-02-05

Multinail Australia

Multinail Hub - Roof Battens Supporting Tiles27 May 2020


Roof Battens Supporting Tiles

Roof Battens to Truss Top Chords

Batten size and fixing to be determined by the truss spacing roof sheetingmaterial, timber type for batten, truss and wind loading. Refer to AS2050,Installation on roof tiles, for batten size and fixings.

Each batten must be fixed to each truss that it butts against.

The following details are provided as a guide only.

Notes:

Multinail recommends that all tile roofs be sarked to prevent moisture enteringthe roof space. It is mandatory that all roofs be sarked as perrecommendations in the Building Code of Australia and AS2050 “Installation ofroof tiles” which includes but is not limited to all roofs in a wind speed areagreater than N3. Refer to tile manufactures recommendations for furtherinformation.

Figure C1-04-04-01


Multinail Australia

Multinail Hub - Roof Battens27 May 2020


Roof Battens

A roof or tile batten is a small section of timber or steel, which is fixed to rooftrusses or rafters to support roof sheeting or tiles.

The size, spacing and fixing of roof battens or purlins shall be in accordancewith the relevant code approved specifications. The batten and fixing musthave adequate strength to laterally restrain the roof trusses. Fix each batten toevery lamination of every truss.

In addition to providing support to the roof cladding, roof battens prevent trusstop chords from buckling. The buckling action is due to the compressive forcein the top chord of the roof truss. The roof battens resist buckling action, whichin turn transfers it to the steel roof bracing and down to the supporting structure.Each element and fixing in the sequence is essential for roof structure stability.

In areas where battens or purlins are not bound on both sides by diagonalbracing, battens shall be continuous (see Figure C1-04-01-01).

Where required, splices in battens shall be arranged so no more than one-thirdof battens are spliced and no two splices are adjacent in any top chord.

For more information, refer to Multinail Technical recommendations for RoofBattens.

Figure C1-04-01-01


Multinail Australia

Multinail Hub - Special Tie Down27 May 2020


Special Tie Down

When the uplift on a truss exceeds 2/Cyclone ties the software states the tie-down required as special. This usually means an engineer is required to review the tie-down at this location. Figure C1-08-01-01 and Figure C1-08-01-02 show alternative fixing details that could be used if a special tie-down is reported.

Figure C1-08-01-01

Treated rods Tie Down Capacity kN

Single Truss

2/M10 33

1/M16 33

Figure C1-08-01-02

Treated rods Tie Down Capacity kN

Single Truss Multiple Trusses

2/M10 30 NA

2/M12 40 54

Threaded rod detail from AS1684 -2010, Table 9.21, detail (h). JD4 Joint Group


Multinail Australia

Multinail Hub - Splice Detail For Roof Battens Supporting SheetSteel27 May 2020

Due to continual product improvement Multinail Australia Pty Ltd. reserves the right to change the product/s depicted - both in description and specification.

Splice Detail For Roof Battens Supporting Sheet Steel

Figure C1-04-03-01

Figure C1-04-03-02

MHS50150


Truss centres 600mm maximum

Batten type 35x70mm minimum

Batten spacing 600mm maximum

Design wind velocity N4/C2 maximum

MHS64100






MHS64150






Notes:

Splices plates must be located centrally on the batten and centrallyacross the joint.Splices may be located anywhere along the batten provided they donot clash with the fixing of the batten to trusses/rafters. (Refer toRoof Batten Splicing Criteria)Adjacent battens should not be spliced in the same panel.Unspliced lengths of battens should be continuous over 3 or morespans.Batten to be designed as per AS1684.


This document has to be read in conjunction with Multinail’s Technical Manual.

Multinail Australia

Multinail Hub - Steel Roof Battens27 May 2020


Steel Roof Battens

Structural purpose

In addition to providing support to the roof cladding, roof battensplay a critical role preventing truss top chord from buckling, e.g.acting as lateral restraints. Continuous buckling can cause bendingof the top chord and collapsing of the roofing structure as thedesign capacity has been reduced.The buckling sideways action is due to the compressive force in thetop chord of the roof truss when under load.Roof battens are also used to transmit the horizontal loads to thebracing system.The effect of the concentrated live load is much greater than theuniformly distributed live load for conventional truss and battenspacing. For the concentrated load, some load redistribution willtake place between battens and trusses.

Refer to the following Australian standards for more information

AS 4440, (Installation of nailplated timber roof trusses), Clause 4.2Roof battens.AS 2050, (Installation of roof tiles) Clause 2.2 Battens.AS 3623, (Domestic metal framing)AS 1684, Residential timber-framed construction.

Installation of steel roof battens

For fixing steel roof battens to truss or rafter at least two fasteners are requiredat each lamination of every truss. Fixing is not to be through top of metalbatten but on each side. (See Figure C1-04-06-03)

Figure C1-04-06-01

Splices in battens

Rules given in AS4440 and “The Guide” must also be followed which include:

Do not splice battens on girder trussesFix each batten to every lamination of every truss with min. 2/nailsAdjacent battens should not be spliced in the same pointNot more than 1 in 3 battens to be spliced on any truss top chord

Note:

Builders, contractors and designers should follow the steel battenmanufacturer’s recommendations regarding installation details.

The correct steel batten installation requires two fasteners at each connection

Figure C1-04-06-02 Figure C1-04-06-03


Multinail Hub - Bearing Plate

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