MARCH 2016 ISSUE: 77WWW.TRADEMAX.CO.ZA SA R36 EACH INCL. / R360 PER ANNUM INCL.

MARCH 2016 ISSUE: 77

EDITOR’S COMMENTS ..................................................................................................... 2

CONTRIBUTORS & EVENTS .......................................................................................... 4

ROOF INSPECTIONS .................................................................................................... 8-9

PROJECT FEATURE .................................................................................................... 10-14

METAL ROOFING ....................................................................................................... 16-17

INSULATION NEWS ....................................................................................................... 18

SAISC STEEL AWARDS ................................................................................................... 19

THATCH ........................................................................................................................ 22-23

STAINLESS STEEL ROOFING .................................................................................. 24-27

SOLAR PV ......................................................................................................................28-29

SEALANTS .....................................................................................................................30-31

WATERPROOFING PRODUCT NEWS ............................................................... 32-33

SLATE ROOFING ........................................................................................................34-36

SAFETY TECHNOLOGY ................................................................................................ 38

SAFETY UPDATE ............................................................................................................... 40

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Trademax Publications

SA Roofing Tel: 0861 SA ROOF (0861 727 663) Fax: 0866 991 346Email: info@trademax.co.zawww.trademax.co.za

Postnet Suite 241 Private Bag X103 N1 City

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PUBLISHER: Billy Perrin

082 266 6976

billy@trademax.co.za

EDITOR: Celéste Perrin

editor@trademax.co.za

ADVERTISING: Jacqui Marsh

jacqui@trademax.co.za

LAYOUT & DESIGN: Craig Patterson

craig@trademax.co.za

SUBSCRIPTIONS: Belinda Thwesha

belinda@trademax.co.za

DISCLAIMER The views expressed herein are not necessarily those of Trademax Publications. Although we have done our best to ensure the accuracy of our content, neither Trademax Publications nor SA Roofing magazine will be held liable for any views expressed or information disseminated, in editorial content or advertisements, in this issue.

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What a wonderful memory that is – my mouth working overtime on nougat, caramel, white, brown and dark chocolate. Yum-yum! (Forgive me – that’s my

sweet tooth talking.) But what, you may wonder, made me think of that? Well, it’s this issue of SA Roofing. The features in this edition cover the gamut of the roofing sector – from slate to thatch to stainless steel (and what a brilliant material it is, as I have learned courtesy of the highly informative sassda series of articles concluding this month) to sealants; I’d say that’s a pretty good mix.

Something else that’s mixed, is sentiment within the industry. Our team hears from and talks directly to you, the professional roofers and associated partners, every day. And we listen. So, we have a fairly good, meaning informed, idea of what is happening and what is not happening out there in your world.

Right now it’s a mix of sweet and dark. It’s becoming more evident, as this year gallops along, that some industry sectors are going through a much more difficult economic time than others. To those enjoying milk chocolate, well done and congratulations. If you choose SA Roofing as your trade print media partner, we’ll show off your accomplishments to inspire others. To those chewing on some bitter-sweet chocolate, hang in there and continue doing what you do best. If you choose SA Roofing as your trade print media partner, we’ll keep you in the eye to inspire others. Because we understand that work, commerce, play – life, actually, is a mixed bag. We experience it too.

Welcome to the March 2016 issue of SA Roofing. Whether a reader or an advertiser, we thank you for your valued support. And whatever your pick, I hope you enjoy the read.

Celéste

Pic-a-Mix Everyone who knows me knows that I have a sweet tooth. Personally, I’d go as far as saying that I have a mouth filled with sweet teeth. I remember well, as a small child, going to town with my Ouma every month to pay for water and lights – and to sneak a visit to the OK Bazaar’s sweets counter for a decadent

treat: I was allowed a monthly ‘pic-a-mix.’

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Lyndsay Cotton entered the construction industry in 1989 as a technical assistant at the City Council of Pretoria. He graduated in 1992 with a BSc (QS) degree and obtained a diploma in project management shortly thereafter. Cotton has constructed well over 300 residential projects (upmarket complexes and ultra luxury individual residential units) and is well versed in residential construction – especially with regards to roofing. He was part of the team that established LCP Roofing (Pty) Ltd. in 2010. Today the company boasts, among other achievements, the SANS1900 accreditation for monoplaner prefabricated timber roof trusses (nail plated). Cotton is also the current Chairman of and serving on the Board of Directors for the ITC-SA (Institute for Timber Construction SA).

Andrew Whitaker developed his keen interest in slate roofs in the early 1980s after obtaining his degree in geology from the University of Cape Town (UCT). He moved to London, and from 1985 to 1992 he worked there as a carpenter and roofer in the construction industry before relocating to France. During the 10 years he spent in that country he gained specialist knowledge in slate, restoring more than 50 farmhouses and historical buildings – all of which had conventional slate roofs. His return to South Africa provided an ideal opportunity to apply the vast amount of knowledge he had gained in Europe, and in a natural progression of his passionate expression of conventional slate roofing, he formed Naturally Slate in 2003. Backed by his leadership and applied experience, the company today prides itself on being a preferred partner in slate installation and maintenance in South Africa.

LYNDSAY COTTON

ANDREW WHITAKER

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Upcoming EventsAFSA INTERNATIONAL ALUMINIUM CONFERENCE & EXHIBITION16 – 18 MARCH 2016 | LAGOON BEACH HOTEL, CAPE TOWNVisit www.afsa-aluminium-conference.co.za for more info

THATCHERS ASSOCIATION OF SA (TASA) 10TH ANNIVERSARY + LAUNCH OF TASA’S “GUIDE TO THATCH CONSTRUCTION IN SOUTH AFRICA”23 APRIL 2016 | FOREVER HOTEL, CENTURIONEmail admin@sa-thatchers.co.za for more info or visit www.sa-thatchers.co.za

HOUSING FOR AFRICA CONFERENCE & TOTALLY CONCRETE EXPO9 - 11 MAY 2016 | GALLAGHER CONVENTION CENTRE, MIDRAND, JHBVisit www.totallyconcrete.co.za and www.construction-week.com for more info

A-OSH EXPO SOUTH AFRICA 201624 – 26 MAY 2016 | GALLAGHER CONVENTION CENTRE, MIDRAND, JHBVisit www.aosh.co.za for more info

WOODEX FOR AFRICA9 – 11 JUNE 2016 | GALLAGHER CONVENTION CENTRE, MIDRAND, JHBVisit www.woodexforafrica.com for more info

CAPE CONSTRUCTION CONFERENCE & TRADE EXPO11 – 12 AUGUST 2016 | CTICC, CAPE TOWNVisit www.cape-construction.co.za for more info

INTERBUILD AFRICA 2016 (CO-LOCATED SHOWS: GLASS EXPO AFRICA, PLUMBDRAIN AFRICA, ECOAFRIBUILD AND HARDEX AFRICA)

17 – 20 AUGUST 2016, EXPO CENTRE NASREC, JHBVisit www.interbuild.co.za for more info

NEW! WOOD WORLD SOUTH AFRICA (RUNNING ALONGSIDE INTERBUILD AFRICA 2016 IN HALL 5)Visit www.woodworldsa.co.za for more info

Call 011 883 0119 or see sassda.co.za. Your complete stainless information source.

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BACKGROUNDThe complainant in this case was the owner of a coastal home. The homeowner resided far away from the residence, but it was occupied by tenants. The respondent in the matter was a registered engineering technologist.

While the two units of the home were occupied by the tenants, various defects became manifest – mostly leakage through the roof into the interior of the units.

The owner commissioned a local home maintenance firm to inspect the roof and make the necessary repairs. After repairs were done, the owner required an Engineer’s Certificate to confirm that the repairs had been done correctly.

The respondent issued a certificate, but it soon became clear that the standard of the repair work that had been done was unacceptable.

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remedial workThe following case study, shared here courtesy of the Engineering Council of South Africa (ECSA), highlights the specialized nature of timber roof

structures using nail plate, as well as the importance of appointing only a qualified entity that is proven to be sufficiently competent to asses prior

roof work done and recommend remedial work.

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Even as the problems persisted, the homeowner’s property insurance claim was rejected. ECSA received the complaint and appointed a specialist to investigate. Shortly thereafter, numerous deficiencies in the original design, which had not been addressed in the repairs and which were not acceptable, were revealed. ECSA found the respondent guilty of breaching the ECSA Rules of Conduct, specifically the terms of Clause 3.

DETAILS OF THE PROBLEM The owner used a local home maintenance company to assess the condition of the existing roof structure and to quote for carrying out the requisite repairs. The owner also requested that an engineer advise on the correct manner to proceed with the roof repairs. The respondent duly attended a site inspection along with the maintenance company representative, and recorded the following observations regarding the condition of the roof:

• Visible (approximately 75mm) deflection of trusses spanning across an open plan area, and exceeding span/240 or 40mm.

• No visible deflection of trusses across smaller rooms, being supported by internal walls.

• Evidence of unsuccessful previous attempts to rectify or strengthen the roof trusses (no details given).

• There appeared to be no firewall between the two units.

The respondent went on to make recommendations for the remedial work, which included:

• Remove roof tiles to reduce load on the trusses, with one unit vacated at a time.

• Brick up the firewall to provide support to a proposed laminated beam to be erected under long-spanning trusses.

• Build up a brick pier into the roof space to provide support to the laminated beam at its opposite end.

• Jack up the long-spanning trusses and position a laminated timber beam under the apex of each truss of size 511mm deep x 65mm wide or 444mm deep x 90mm wide.

• Reuse existing brandering, provide white PVC underlay, and repack tiles.

• Fit storm clips to the bottom two rows of tiles on each side of the roof.

The quotation by the home maintenance company representative took the above recommendations into account, but specified a laminated beam of size 320mm deep x 114mm wide. If the roof structure required replacing, the cost would be approximately double that of the quotation. The respondent signed a Certificate in terms of the National Building Regulations, thereby confirming the structural system had been completed in accordance with the application in respect of which approval was granted in terms of Section 7 of the National Building Regulations and Building Standards Act. Subsequent to this, the tenants in the unit advised the owner that problems with the roof were continuing, including possible damage to the roof. The owner submitted a claim to the insurers of the units, which was rejected. The insurers advised that, following an inspection by their own service provider, the damage sustained did not fall within the scope of the policy cover, with the chief reason for leakage being lack of maintenance.

The service provider’s report condemned the repairs, requiring inter alia:

• Repack part of the roof. • Correctly repair seven trusses. • Re-align slipped apex connection (members out of line). • Replace nail plates not hammered across joints. • Avoid wedges under battens to level roof. • Correct roof covering tiles, needing another batten and

extra tiles each side of ridge.

ECSA INTERVENTION After receiving the complaint, ECSA commissioned a specialist engineer to investigate and report on the matter. The investigation confirmed the deficiencies as mentioned, and the report included the following findings:

1. Poor fabrication and embedment of nail plates. 2. Randomly sized nail plates with random orientations. 3. Internal walls used as internal supports. 4. Trusses undersized to span 10.45m over full width of unit. 5. Ridge tiles not adequately covering roof tiles. 6. No rafter or web runner bracing for long-term stability. 7. Laminated beam inadequate and overstressed. 8. Site application nail plates not 30% longer than machine

plates. 9. SABS 0243 (Design, Fabrication & Erection of Timber Roof

Trusses) not complied with.

It was determined that the original truss fabrication and erection was of very poor quality. Moreover, the remedial work recommended by the respondent was inadequate to stabilize the roof in the long term. The work was not inspected by the respondent prior to issuing a stability completion certificate; the respondent had chosen to rely on the builder’s integrity. Finally, new trusses should have been manufactured and installed in the roof.

With regard to ECSA’s Rules of Conduct for Registered Persons, it was apparent to the investigators that the respondent had transgressed several of the Rules as related to competency, integrity, public interest as well as the dignity of the profession.

CONCLUSIONThe design, fabrication and erection of timber roof structures using nail plate is a specialized area of structural engineering and should not be undertaken lightly. In particular, this applies to the assessment of the condition of existing roof structures and the design and specification of remedial works.

ECSA maintains a strict code of conduct for all its members and can assist in the proper appointment of a qualified engineer to perform these specialist duties.

Disclaimer: This case study is intended as general information only, not as specific professional advice – legal or otherwise. Every situation should be considered separately and specific professional advice in relation thereto should be sought.

For more information, visit the ECSA website at www.ecsa.co.za.

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Behind the scenes of Agri-Hub Office ParkThis stellar project was entered into the 2016 Concrete Manufacturers

Association, NPC (CMA) Awards for Excellence competition. Judging for the competition has closed, and we are now looking forward to 23 April 2016 when the winners will be announced. Here, Lyndsay Cotton shares some

insight into a few specifics that contributed to the quality result.

Article by: Lyndsay Cotton, Chairman of the ITC-SA (Institute for Timber Construction SA) and General Manager of LCP Roofing (Pty) Ltd.

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The Agri-Hub Office Park consists of three main buildings with duo-pitch concrete tiled roofs, each with an additional elliptical mono-pitch slate roof supported on

laminated beams. A fourth, circular building with a mono-pitch roof consisting of inverted mono trusses and covered with slate, completes the formation.

DESIGN SPECIFICATIONS Trusses are mostly designed with one pinned support and at least one roller support. From a design calculation point of view, the roller support will allow the truss to move horizontally; therefore, the truss design needs to ensure that the truss is stiff enough for the horizontal movement to be kept to a minimum or at least within acceptable design standards. When a truss is designed with one support pinned and the other support as a roller support, the design calculations will show that there are no horizontal reactions.

For several reasons, including making sure that the construction completion deadline would be met, the designers of the

building opted for a structural steel ring beam in lieu of the more common concrete ring beam on concrete columns.

The Agri-Hub Office Park project illustrates that there are instances where a pinned support is required at both truss supports. By pinning both supports, the roof truss is then dependent on the supporting structure, as well as the connection of the truss to the supporting structure, for its strength. The supporting structure must therefore be able to withstand all the vertical forces as well as the horizontal forces imposed on it by the roof structure.

The structural steel ring beam on the concrete columns was optimally designed in terms of size and cost, but was not able to resist the horizontal buckling moment of 5kN of the trusses imposed on it. The truss design had to accommodate this requirement: Each timber heel-to-steel beam connection was designed to be a bolted cleat connection consisting of a 5mm flange cleat at the truss heel, and 4xM12 bolts with standard square washers on the timber face.

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Architectural design requirements called for cantilever trusses and closed eaves. With the overhangs of 1,540mm on the run and 1,400mm on the hip face, it means the hip corner girders do not lie exactly on the corner of the structure, but are slightly offset.

Cantilever trusses are designed with the overhang horizontal distances taken into account. But, critically, the hip ends need special attention as this horizontal distance is significantly longer than the horizontal distance of the eaves’ overhang.

No cantilever truss or hip, within a hip system, can be cost-effectively or at times practically designed without an eaves beam. Typically, without an eaves beam, the hip ends will sag due to loads imposed by both dead and live loads such as roof coverings or foot traffic for maintenance purposes. The purpose of an eaves beam is to assist in transferring the hip system loads to the trusses adjoining the hip system. The connections of the eaves beam to the hip trusses are also vitally important, and nailing only is generally insufficient.

(to support large corner overhangs)

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The specification of suspended ceilings, which are typical in commercial buildings, meant that bottom cord bracing had to receive specific attention in terms of truss design, standard bracing rules and SANS10400.

Allowance also had to be made for electrical cable trays, and air-conditioning ducting of approximately 30kg/metre were specified. Maximum imposed loads of 50kg per air-conditioning unit were allowed at specifically indicated positions.

After considering various practical options, the Aveng Manufacturing Infraset (Horizon™) concrete roof tile was specified by the client as the roof covering of choice. The resultant aesthetic appeal has received many compliments.

For more information, visit www.agri-hub.co.za or send an email to the author at lyndsay@lcproofing.co.za.

PROJECT TEAMPROJECT NAME: Agri-Hub Office Park LOCATION: 477 Witherite Road, Die Wilgers, Pretoria, 0184BUILDING OWNER: Grain Building (Pty) Ltd. (L-lagric@mweb.co.za)DEVELOPER: Elmado Property Projects(Director, Francois Barnard: francois@elmadogroup.co.za) ARCHITECTURAL DESIGN: Royal HaskoningDHV(Principal-Specialist Architect, Mauritz Kruger (Pr. Arch): mauritz.kruger@rhdhv.com)ENGINEER: DG Consulting Engineers (Director, Johan du Plessis: johandup@dgconsult.co.za) QUANTITY SURVEYOR: Quanticost Pretoria(Director, Willie Fourie: willie@quanticostpta.co.za) MAIN CONTRACTOR: JT Son Construction(Director, Richard Franks: richard@jtson.co.za) SUBCONTRACTOR (FABRICATOR AND ERECTOR): LCP Roofing (Pty) Ltdwww.lcproofing.co.za(General Manager, Lyndsay Cotton: lyndsay@lcproofing.co.za)ROOF COVERING PRODUCT MANUFACTURER: Aveng Manufacturing Infraset: www.infraset.co.za

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8302 - LAMBDABOARD (DICE) A4 ADVERT Paths.indd 1 2015/10/14 11:45 AM

In addition to material selection and the roofing profile required (whether for cladding or roofing), consideration must be given to roof ventilation as well as rooftop fitments like solar arrays, satellite

dishes, or heavy HVAC units. All these factors should be considered at the design stage, and the performance of the total roof ‘system’ should be regarded as a single investment by property owners, investors and occupants alike.

CHOOSING THE RIGHT ROOFING MATERIALMetal roofing is the choice of architects on the cutting edge of green. Not only is steel roofing cost effective, it also contributes to sustainability: Metal roofing is 100% recyclable at the end of its useful life. However, not all metal roofing is the same.

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Why detailed specification matters

in metal roofing The design of a roof system demands a detailed and fastidious focus on

every system component in order to make the most of its potential as the hardest working part of the building envelope. Safintra Roofing tells us more.

The Classicor® Corrugated Profile is both timeless and contemporary.

Safintra offers a range of Aluminium-Zinc Ventilators.

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When it comes to coated steel, aluminium-zinc coated metal roofing has huge benefits over traditional galvanized material, including a longer service life and superior thermal efficiency, which delivers savings towards the heating and cooling costs of buildings. For extremely corrosive environments or specialized applications, aluminium (painted or unpainted) and Rheinzink® (titanium zinc) provide uniquely extended lifespans.

CHOOSING THE RIGHT PROFILEMetal expands at approximately 1mm per metre, so when using long lengths, natural thermal expansion and contraction can be a serious concern – particularly where there are significant differences in daytime and evening temperatures.

This is where concealed fix systems such as Saflok™ or a standing seam system such as Newlok™ is ideal. These systems have hidden clips, anchors and other attachments allowing for thermal movement, and can withstand challenging wind conditions. These profiles are also aesthetically pleasing.

CHOOSING APPROPRIATE FASTENERS Just as important as selecting the correct sheeting materials and profiles, is selecting fasteners of optimal quality. For pierced fix applications, nothing less than Fixtite® or Safintra-approved Class 4 fasteners are recommended.

For the attachment of anchoring or clamping systems with concealed or standing seam, where the fasteners are not exposed to external weather conditions, a Class 3 fastener is more than adequate.

INSIST ON ONLY THE BEST FLASHINGS AND VENTILATORSFlashings are primarily intended as those components of a roof that ensure water-tightness. (But yes, they can be for aesthetics too.)

If penetration is necessitated by the installation of rooftop cooling systems, or HVAC installations, designers and contractors need to ensure that suitable materials are used so as not to void material warranties. They should also have a service life that reduces frequent maintenance.

Safintra makes flashings for all their profiles, using materials that match the roof sheeting, thereby extending the service life of the entire roof system. The company also produces handmade, bespoke ventilators and louvres unique to each project, with warranties that match the sheeting lifespan.

ENSURING COMPLETELY SERVICEABLE ROOFSRoofs are subjected to regular foot traffic as well as the loads imposed by the installation of rooftop utilities. As a professional, you should request technical support to ensure that the roof is serviceable and practical for rooftop installations and for routine maintenance.

Safintra, whose business is founded on a strong technical focus, is proud to offer this service free of charge to its South African customers from seven branches countrywide. Branches in SA: Johannesburg, Durban, Cape Town, Nelspruit, Polokwane, Port Elizabeth, and Bloemfontein.

Further operations in: Namibia, Botswana, Zambia, Mozambique, Malawi, Tanzania, and East Africa.

For more information, visit www.safintra.co.za.

Cladding in the Saflok® 410 Profile adds a touch of distinction.

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BACKGROUND OF SAEE

Founded in 2002, the SAEE is a non-profit coordinating body for energy efficiency in Southern Africa. Their work encompasses an umbrella focus towards the continuous efficient use of energy to support the viability and sustainability of a healthy energy mix and energy-efficient businesses.

SAEE’s focus is on growth while enhancing business sustainability with a specific focus on energy use.

The SAEE includes various divisions, namely the Measurement and Verification Council of South Africa (MVCSA), Southern African Females in Energy Efficiency (SAFEE), Energy Services Companies (ESCOs), and now of course the Thermal Insulation Products & Systems Association SA (TIPSASA).

MEASUREMENT AND VERIFICATION COUNCIL OF SOUTH AFRICA (MVCSA)

The SAEE established the MVCSA as an independent body to ensure that credible and transparent quantification of energy and efficiency savings are reported. The quality of services rendered by the Measurement and Verification Council members and related service providers are held to the highest standards.

SOUTHERN AFRICAN FEMALES IN ENERGY EFFICIENCY (SAFEE)

The SAEE believes that equity in the workplace is of major importance. However, some women in energy efficiency may struggle to find their feet. Advice, guidance and/or mentorship from experienced and knowledgeable individuals can make all the difference in a young woman’s success. The Females in Energy Efficiency (FEE) initiative focuses on opening the energy efficiency industry to all women interested in participating in this space.

ENERGY SERVICE COMPANIES (ESCOS)

Energy efficiency would not be possible without those who evaluate current practices, equipment and conditions, propose solutions, and – most importantly – implement the proposed energy efficiency measures. It therefore makes sense that ESCOs should be part of the SAEE.

THERMAL INSULATION PRODUCTS & SYSTEMS ASSOCIATION SA (TIPSASA)

TIPSASA, the latest addition to the SAEE ‘family,’ focuses on the thermal insulation industry, with particular emphasis on energy-efficient products and systems. As a non-profit company it will continue to serve its members, professionals, as well as consumers.

The conservation of energy is of paramount importance and thus the education on the usage and correct installation of thermal insulation products and systems is vital. The best insulation product or system can be ruined if not correctly installed. TIPSASA, together with two accredited training providers, will embark on a new training initiative in 2016.

FOR MORE INFORMATION:

TIPSASADes Schnetler (t) (+27) 12 663 5200 Ext. 232(f) (+27) 684 306186(e) tipsasa@mweb.co.za (w) www.tipsasa.co.za

SAEELydia Marais (t) (+27) 11 038 4300(f) (+27) 86 513 2957(e) admin@saee.org.za (w) www.saee.org.za

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The official affiliation of the Thermal Insulation Products & Systems Association SA (TIPSASA) with SAEE (The Southern African Association for

Energy Efficiency) was announced at the SAEEC 2015 Banquet. TIPSASA will be known as a division of the SAEE. TIPSASA’s primary focus will remain on

thermal insulation products and systems for the building envelope.

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The deadline for entries is Thursday, 21 April 2016. However, a 10% early-bird discount is being offered for complete entries that arrive at SAISC on or before

Thursday the 14th April 2016.

SAISC CEO, Paolo Trinchero, says this is a very special year for the Steel Awards as it will be celebrating, inter alia, SAISC’s 60th year. “We expect that the industry will respond positively to this being the 60th year of the Institute’s existence and we expect more entries than ever. In spite of challenging times over the last couple of years, there is no doubt that there are still many projects being done in and around South Africa that prove that the standard of steel construction in our region is as good as anywhere in the world. We look forward to seeing them in Steel Awards 2016,” he says.

Trinchero adds that the single main criterion of an entry into Steel Awards is whether the project illustrates clearly what can be achieved with steel. The main condition of entry is that the steelwork should essentially have been completed in 2015.

STANDARD PROJECT ENTRY FEES: • Projects of 10t or less: A fixed fee of R925 (incl. VAT)• Large projects more than 10t: Fixed fee of R3,600 (incl. VAT)

Benefits for entrants of large projects include one complimentary seat at the Steel Awards dinner at the venue of their choice, i.e. Johannesburg, Durban or Cape Town, on condition of booking more than one seat in total, as well as a 5% discount on any advertisement placed in the special Steel Construction edition, which will be distributed at the Steel Awards dinner.

Note: The material to be submitted by deadline must include the fully completed entry form (in MS Word) with full and accurate details of all project team members, 6 - 20 quality images (including one to consider for the annual photographic competition), and a project description and entry motivation.

For full information on project entries or sponsorship opportunities, email Marlé Lötter at marle@saisc.co.za.

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Call for entries for Steel Awards 2016

The Southern African Institute of Steel Construction (SAISC) has called for entries for Steel Awards 2016, which will take place simultaneously in

Johannesburg, Durban and Cape Town on 15 September 2016.

Steel leaves a legacy.

SOUTHERN AFRICAN INSTITUTE OFSTEEL CONSTRUCTION

Southern African Institute of Steel ConstructionTel: +27 11 726 6111

Email: info@saisc.co.za www.saisc.co.za

Crossing Bridges

Whether it’s intricate community bridges, massive mining headgear, revolutionary light steel frame restaurants, innovative multi-storey modular technology, state-of-the-art computerised fabrication technology, expert international export strategy or training industry personnel in the latest techniques of the steel construction trade, the Southern African Steel Construction Industry can be proud of the bridges it has crossed to become a world class industry.

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SA Roofing is pleased to showcase this world-class thatch installation here, with some added insight from the owner of Recon Thatchers, J A (Bertus)

Nieuwenhuis.

Nieuwenhuis is also the outgoing National Chairman of TASA (the Thatchers Association of South Africa). TASA will be announcing the appointment of their new chairman at their upcoming AGM being held on 23 April 2016.

As with any project, everything starts at the drawing board. The preliminary engineering drawings reflect the high level of complexity this project held, with the thatch roof at 1,398m2 measured on the drip line. And that is not to mention starting with pole structures between 10m - 13m in height, which posed challenges of their own.

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Best in the world is right here

Recon Thatchers won the coveted International Best Thatched Roof Competition Award during the International Thatching Society's Congress in

2015 for their work done on the Letsatsi Game Lodge. It’s good to know that their stellar workmanship is readily available right here in South Africa.

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• The pole structures were erected at 45 degrees.• Dormer windows were installed in such a way so as to

promote easy water flow from the roof. • All structures were constructed in accordance with SANS-

10407.• A fire blanket was installed, preventing fire from spreading

from the inside to the outside of the thatch roof. The fire blanket can withstand heat of up to 550-700 degrees Celsius.

• Special care was taken to ensure the highest aesthetic delivery across the entire structure – from the edges of the roof to the valleys, around the dormer windows, as well as on the ridging.

• Care was taken to ensure that all lines were straight with no bumps or dents.

• Additional care was taken to apply neatly laid sprei-reed not only on the roof, but also into the roof to complement the Africa theme.

The final product was pleasing, not only to the eye and for the public’s enjoyment, but also to Recon Thatchers. It gave the company a sense that their team has what it takes to be the best. And their International Best Thatched Roof Award proves it.

For more information, visit www.reconthatchers.co.za.

Building plan: © M du Plessis, Pr Teg (Ing) (Bloemfontein)

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The summer of 1886…Transvaal, South Africa. George Harrison and George Walker discover gold just south of a small ridge called the Witwatersrand, on a farm named

Langlaagte.

News spread quickly and within mere months, public diggings were declared on several farms. As a flood of adventurers and fortune seekers set their sights on that isolated piece of African savannah, shelters were made of anything that came to hand, including mud and grass.

THAT WAS THENIn October 1886 the name Johannesburg was used for the first time, and Randjeslaagte was proclaimed as a village of stands.

On 8 December 1886, the first sale of stands in Johannesburg took place (most going for around £10.10). More permanent structures started going up, seeing the use of corrugated iron as roofing material.

In 1888, the fledgling town received its first electricity supply, telephones and piped water, and on 14 September 1892 the first train from the Cape reached Johannesburg. Soon new housing was spreading in every direction, especially houses with corrugated iron roofs projecting over their fronts to provide shade against the harsh Highveld sun. This style of home, with its veranda (or ‘stoep’ in local parlance) became the Transvaal vernacular in architecture. In the town centre, however, buildings more stylistically at home in London than on an African plain were sprouting – each one a tribute to the stonemasons’ craft, but all with corrugated iron roofs.

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– Part 3 In this last instalment of a three-part series of articles by the Southern Africa Stainless Steel Development Association (sassda), we take a trip

down memory lane that leads us back to different roofing options available today, we make some comparisons, and finally we take a ‘101’ in that very

important construction concept, Life Cycle Costing.

The NASCAR Hall of Fame. The ‘Ribbon’ architectural element wraps around the building in an expression of the imagery, spirit and speed associated with the sport of car racing. It comprises 5,000 panels made of stainless steel in a lustrous angel-hair finish that softly reflects light.

Photo credit: Nick Ledford

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Even Randlord Lionel Phillips’ mansion, Hohenheim, that was built in 1892, sported the ubiquitous corrugated iron roof. And, for another couple of decades, corrugated steel roofing reigned supreme in South Africa.

THIS IS NOWIn time, clay tiles replaced corrugated steel as the residential roof material of choice. However, commercial buildings stayed loyal to profiled steel roof sheeting, because of their larger areas and also because they are not as susceptible to fashion trends. Initially, ‘standard’ corrugated sheets were used universally. The common standard for corrugated sheet now is a roll-formed profile with 10.5 corrugations at 76mm centres, giving a net cover of 762mm.

This has been superseded in most applications by Inverted Box Rib, or IBR. The defining characteristic of the IBR profile is the wide pan between the ribs. This makes it suitable for lower pitches thus able to channel large amounts of water from the roof to run-off points. The profile is common in commercial and industrial establishments like malls and factories. This profile can be used for both normal roofing and cladding.

One of the metal roofing profiles rapidly gaining ground is concealed fix sheeting. The sheets are laid without being screwed down. Clips are used to fix the sheets to battens or purlins. These profiles are ideal for low pitches and are able to channel water effectively. This profile may be more expensive than other profiles, but offers leak-proof cover.

Many manufacturers offer the option of rolling the sheeting on site, so you may be able to have a single sheet spanning the roof length.

Also now available are special clips or brackets allowing for the installation of solar panels on the roof without drilling mounting holes.

Although metal roofs usually have a warranty of at least 30 years, the gaining popularity of steel roof sheeting in South Africa is largely because of the energy efficiency of this roof type.

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MANY MATERIALS HAVE BEEN USED FOR ROOFING:THATCH: Wheat straw, Seagrass, Rye, Raffia palm, Rice straw, Water reedSHINGLE: Wood, Shake, Slate, Asphalt, Rubber, Asbestos, Stone, MetalCERAMIC TILE: Dutch, British, Mangalore (India)MEMBRANE: Thermoset (e.g. EPDM rubber), Thermoplastics (PVC, TPO, CSPE), PTFE(synthetic fluoropolymer) embedded in fibreglass METAL: Corrugated galvanized iron, Copper, Standing-seam metal with concealed fasteners, Mechanically seamed metal with concealed fasteners, Flat seam metal, Stainless steelCONCRETE: Structural concrete (for flat roofs)

Oval and slightly cone-shaped office building in Scheppach, Southern Germany. Photo credit: Detlef Schobert

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LIFE CYCLES AND OTHER CONSIDERATIONS Wood shingles have a life expectancy of up to 30 years, whereas slate could last up to 400 years. Rubber shingles have been known to last 50 years. Ceramic tiles have a lifespan of more than 100 years.

From the end of the 19th century, asbestos was the darling of the construction industry. Its diverse applications included fire retardant coatings, concrete, bricks, pipes and fireplace cement, heat, fire, and acid-resistant gaskets, pipe insulation, ceiling insulation, fireproof drywall, flooring, roofing, lawn furniture, and drywall joint compound.

Then, the material fell foul because of its health hazard. Despite a ban on asbestos products some years earlier, in 2011 it was estimated that more than half of all homes in the United Kingdom still contained asbestos.

In the end, metal roofing remains the most popular choice because of cost, ease of erection, energy performance, light weight and longevity.

IS STAINLESS STEEL THE ANSWER? The questions remain: Coated steel sheeting or stainless steel? Is stainless steel the most cost-effective solution?

Stainless steel is durable and has low maintenance costs because of its exceptional corrosion resistance. There is no coating or painting requirement, and normal maintenance would simply be occasional cleaning.

Stainless steel may not always be the cheapest candidate material for an application when considering upfront costs. However, its durability and ease of maintenance compensate for the sometimes higher initial purchasing costs, and it is often the least expensive choice in a life cycle costing comparison.

The ability to provide long-term performance with a minimum of downtime and cost associated with maintenance is determined by calculating the material’s life cycle cost. Life cycle costing (LCC) is a technique developed for identifying and quantifying all costs, initial and ongoing, associated with a project or installation over a given period.

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Millennium Centre, Cardiff. Photo credit: Tony Hisgett

Copper-coloured stainless steel tiles that cover the roof of the Millennium Centre, Cardiff. Photo credit: Tony Hisgett

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LIFE CYCLE COSTING (LCC)LCC uses the standard accountancy principle of discounted cash flow, so that total costs incurred during a life cycle period are reduced to present-day values. This allows a realistic comparison to be made between the available options. As far as material selection is concerned, LCC enables potential long-term benefits to be assessed against short-term expediency.

Material costs are assessed with their implications; for example, initial outlay, maintenance and its frequency, downtime effects, production losses, repair, replacement, and other operationally related costs such as manpower and energy consumption.

The LCC model is more than a philosophy of forward thinking. It has been refined to a detailed system of specific calculations to aid decision makers to compare accurate forecasts that have taken all the pertinent factors into consideration.

In general terms, the total LCC can be broken down into the following components:

• Acquisition Cost• Fabrication and Installation Costs• Maintenance Costs (periodic)• Replacement Costs (periodic)• Cost of Lost Production (periodic)• Residual (Scrap) Value

Each of these terms must be known for a realistic result to be calculated. The environment and scope of usage are therefore crucial in determining the LCC benefits when choosing stainless steel.

Stainless steel offers corrosion resistance, fire and heat resistance, strength, toughness, aesthetic appearance, easy fabrication, long-term value, and it is also non-polluting. The stainless steel promise says it all: Stainless Steel. It’s Simply Brilliant!

Should you wish to calculate the LCC of a specific project, the Southern Africa Stainless Steel Development Association (sassda) will be glad to assist.

FOR MORE INFORMATION:

sassda(t) 011 883 0119(w) www.sassda.co.za

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Industrial building in Altdorf near Nürnberg, Germany. Photo credit: Detlef Schobert

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Port Elizabeth-based Dumont Power was established in 2015 as a special-purpose vehicle for the distribution and support of specific solar technologies. It represents

SoloPower Systems and Suncore Photovoltaics.

Company director Raymond du Plooy says it is no longer the case that solar panels cannot be an option for certain roofs, as Dumont Power has introduced a solution via the SoloPower lightweight photovoltaic (LPV) panel.

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solar photovoltaic panel in Africa

“We estimate that as many as 30% of commercial and industrial buildings’ roofs are not able to hold the weight of traditional solar panels, making owners and developers think that solar panels are not an option

for their facilities. This is no longer the case…” – Raymond du Plooy, Director - Dumont Power.

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Cape Composite (Pty) Ltd., a leading manufacturer of fibreglass products, recently installed a new factory roof after a fire destroyed the previous one. While the new roof was unable to hold the weight of normal photovoltaic panels, the SoloPower LPV panels, weighing a mere 2.4kg/m2, became a viable alternative. In fact, phase one of the Cape Composite installation has already been completed – with a total of 304 panels producing 60kWp of power, according to du Plooy.

“The installation itself was quite remarkable, as the product requires no power tools, framing, special handling or other common installation aspects. The installation team, working at a normal pace, installed 1 watt per second. There was no need for special rigging equipment to get the panels in place, and no need for a large storage area to keep the panels before installation. It was really a very simple and fast installation. We even had two uninstalled panels blow off the roof and fall 30m to the ground, but they were completely undamaged,” he says.

Cindy Oberholzer, Financial Director at Cape Composite, adds: “As a company we continually strive to ‘go green,’ to cut down on waste, and curb costs. Traditional glass photovoltaic panels were not an option for us as they were too heavy for our roof structure, which could not support them. We came across SoloPower’s ultra-thin, flexible solar panels, which offered us the perfect solution. The main advantage and reason we decided to go the SoloPower route is because their LPV panels are extremely light. Other positive factors were that the LPV panels were not as fragile as glass.”

Oberholzer says the installation took about two weeks. “Our total roof size is 4,500m2, with the size of the section covered with these lightweight photovoltaic panels being an initial 1,500m2. We are the first company to use SoloPower in South Africa – and the parent company visited us on three occasions in order to assess and monitor the project, which will be an ongoing process by SoloPower. We will be installing the other two-thirds of our roof with these panels in the future.”

BENEFITS OF LPV PANELSSoloPower panels have a CIGS (Copper, Indium, Gallium, Selenium) composition - ideal for thin-film solar applications. Some of the benefits of LPV panels include:

• Low installation costs• High energy performance• Built to meet/exceed UL 1703, IEC 61646 and IEC 61730

standards• Designed for superior performance under all light

conditions, including low-sun angle• Easy to install• Mounted with commercially available adhesives

“We are pleased that Cape Composite took a leap of faith with our SoloPower LPV lightweight panels. They will not be disappointed with the durability and performance of the product. SoloPower in the USA intends to fully assess these projects with Dumont Power, in order to ensure that the performance of these panels is fully optimized to meet customer requirements and expectations,” du Plooy concludes.

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Tel: 011 828 3453 / 3445 / 9126Fax: 011 828 5578

E-mail: info@doublejack.co.zaWebsite: www.doublejackroofing.co.za

(Pty) Ltd

METAL ROOFING & CLADDING SPECIALISTS

Dow Corning structural glazing sealants, supplied by a.b.e. Construction Chemicals (part of

the Chryso Southern Africa Group), were selected for the project. Internationally regarded as the top quality standard for structural glazing, Dow Corning sealants are imported from Belgium by a.b.e., the South African technical distributor for Dow Corning.

Glenn Bouwer, a.b.e.'s Branch and Sales Manager: General Construction in the Western Cape, explains why the Dow Corning 895 one-part structural silicone adhesive and the Dow Corning 813C silicone weather sealant were specified for the refurbishment of the 20-year-old atrium, which reaches a height of 40 metres above the shopping centre's main escalators on the ground floor:

"The old glass panels had started delaminating, and the original sealants had failed in places – resulting in leaks into the shopping complex. Cloud 9 Skylight Solutions removed the old glass panels and aluminium framing, and fitted new powder-coated aluminium frames as well as high-performance NC 55E glass panels,” Bouwer says.

“The new glass panels weigh up to 200 kilograms each, and are made from 13.6mm-thick, toughened glass. The panels were fixed to the aluminium frame at angles of 30 degrees on the roof, and up to 80 degrees on the façade. This challenging installation clearly called for an exceptionally strong structural bond, which is why Dow Corning 895 was specified," he adds.

Dow Corning 813C silicone sealant was subsequently applied as an external weather seal on the atrium façade. In total, Dow Corning sealants were applied to about 800 linear metres of surface area.

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The refurbishment of this towering atrium, the focal point of Cavendish Square Shopping Centre in Claremont, Cape Town, involved a challenging

installation that called for an extremely strong structural bond.

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PRODUCT QUALITIES Dow Corning 895 structural silicone is an odourless, neutral cure product, which exhibits excellent stability through a wide range of temperatures (minus 50 degrees Celsius to 150 degrees Celsius). The cured product has exceptional weathering characteristics with a high resistance to ultra violet (UV) radiation as well as humidity. It can adhere to a wide range of substrates, including powder-coated aluminium, enamelled or reflective glasses, polyester-coated aluminium profiles, as well as stainless steel profiles. All substrates are extensively tested for adhesion, staining, etc. by Dow Corning laboratories in Belgium prior to project starts and, if successful, written approval is issued to the glazier.

Dow Corning 813C, which was used at the Cavendish Square refurbishment project as weatherproofing sealant, is a one-part, neutral curing, low modulus sealant suitable for interior and exterior applications such as weather seals, expansion joints, and perimeter joints in buildings and other types of structures. It has a joint movement capability of + 50%, - 50% and provides strong, unprimed adhesion to various surfaces, including glazed surfaces, concrete, masonry, brick, wood, and some plastics.

WORKMANSHIPCape Town-based Cloud 9 Skylight Solutions has extensive experience in the application of Dow Corning sealants and is an approved DC applicator, currently in the process of finalizing DC ‘Quality Bond Membership,’ a stringent process that can take up to five years to achieve. "Dow Corning guarantees that Quality Bond members provide a level of workmanship and application that meets the company's demanding requirements for safety and durability. Quality Bond applicators are audited annually to have their certification renewed," Bouwer states.

Dow Corning structural glazing silicones hold European Technical Approval (ETA) through independent testing to European Technical Approval Guidelines (ETAG002).

a.b.e. also recently supplied DC silicone sealants for Portside, which at 139 metres high is the tallest office block in Cape Town, for Alice Lane Phase 3, as well as the Protea Place office block in Sandton and the Bank of Mozambique in Maputo.

Dow Corning structural glazing sealants supplied by a.b.e. Construction Chemicals being applied for the refurbishment of the atrium at Cavendish

Square Shopping Centre in Claremont, Cape Town.

Effective Reduction of Temperature within Attic Space

Protects against Radiant Heat and UV Penetration

bubble RADIANT HEAT BARRIER

®

A two-component, solvent-free formulation, Purtop HA has been designed for application by hand to form tough elastic waterproofing membranes on small- to medium-sized flat roofs

and terraces. It can also be used to repair surfaces that have been waterproofed with hybrid polyurea or pure polyurea membranes.

PRODUCT QUALITIES The product adheres extremely well to many types of substrates after proper preparation to remove any oil, grease or dirt and, in the case of concrete and screeds, priming with Mapei Primer SN followed by dusting with Quartz 0,5.

Once thoroughly mixed, Purtop HA stays workable for 20 minutes at around 23°C and can be applied easily and quickly to give a neat, seamless 2mm-thick grey membrane that allows light foot traffic within 24 hours.

The hardened product offers extremely good resistance to alkalis, dilute acids and detergents, combined with excellent tensile (10 N/mm2 in terms of DIN 53504) and tear strength (40 N/mm2 according to ISO 34-1).

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manually applied Purtop HA product.

PURTOP HA is initially spread by trowel to the thickness needed to cover the required area (as seen below). The PURTOP HA coat is then smoothed over to give a seamless, smooth finish.

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CASE STUDYIn a recent project, Mapei South Africa was commissioned to provide a solution for a badly cracked flat roof on a house in a Pretoria estate. Mapei South Africa’s technical support team trained a contractor on the project to be a Purtop HA approved applicator. The cracks were ground open and a structural repair carried out using Mapei Epojet LV. The existing substrate was then roughened with cup brush grinders, cleaned, solvent wiped and then primed to ensure a sound mechanical bond for the waterproofing membrane.

The two-component Purtop HA kit was mechanically mixed and poured directly onto the touch-dry primed surface. The product was initially spread with a 5mm notch trowel to gauge the correct thickness, and then carefully smoothed to an impressively neat, seamless finish.

“In keeping with Mapei South Africa’s total solution approach, we offer a range of Mapei primers for different substrates, as well as preparation systems for less than ideal surfaces,” says Paul Nieuwoudt, Mapei South Africa’s Product Manager for Building Systems. “These include cavity repair grouts and epoxy primers to speed up work when residual moisture levels in the substrate are higher than recommended, as well as rust prevention epoxy primers for steel.”

For the past six years, Mapei South Africa’s technical service team has been introducing the local construction industry to the benefits of the advanced building technology additives, sealants, adhesives and concrete performance chemicals that are available from the international Mapei Group. Offering market-leading performance and handling advantages, Mapei’s 1,400 products are recognized throughout Europe, America and the Far East.

PURTOP HA is an easy to mix, two-component solution.

Exposed crack in flat roof that required repairs.

Reg No: CoR18.3 2013/068719/07 VAT No: 4930188372

QUALITY FASTENING SYSTEMSMANUFACTURERS OF

JHB Branch: Contact: Tanny | Tel: 011 - 979 5026/7 | Cell: 082 782 6854 | P.O. Box 14353, Bredell, Kempton Park

Manufactured in Taiwan

DBN Branch: Contact: Summers | Tel/Fax: 031 - 765 1604 | Cell: 082 564 1463 | hengfusa@gmail.com

www.hengfuscrews.co.za

With a passion for slate coupled with a career in the roofing industry that started in 1987, Andrew Whitaker has put his knowledge to good use.

Having personally trained his team of slate roofers, now ably led by John Mashiane for Ottery-based Naturally Slate, this professional line-up boasts restoration work on Valkenberg Hospital, the Castle of Good Hope, and the spectacular tower that adorns the old Castle Brewery in Woodstock – to name but a few assignments.

SA ROOFING: Why is a slate roof a good option for a residence?

WHITAKER: Slate is viewed as an upmarket product, and therefore it enhances the value of a property. In addition, it has a long shelf life and will outlast thatch and sheeted roofs. It is also considered a natural product, which, in today’s eco-friendly world, is an important factor when choosing a roof. Its carbon footprint is regarded as very low.

SA ROOFING: What is the history of slate roofing, and more specifically in South Africa?

WHITAKER: After thatch, slate is the oldest type of roofing material used worldwide. Records show that slate in South Africa was first imported from Wales in the mid-1800s and used as an alternative to thatch. Prior to the Welsh slate importation, most houses in South Africa had thatch roofs.

Many of the old government buildings like the City Hall, Valkenberg and the Houses of Parliament, were initially covered in Welsh slate, while practically all the old houses in areas like Oranjezicht and The Gardens were also roofed in Welsh slate.

South African slate was first used in the 1930s. The size of that slate was similar to the Welsh slate, but it was thicker. As such, its weight on the roof was significant enough that trusses had to be specially designed to hold those conventional roofs.

After World War II and with the advent of bituminous underlay (Malthoid being the most widely used product brand) to provide the waterproof aspect, slates could be cut to a much smaller and therefore a lighter size. This method of slating (the patented Peterlo® system) is still used to this day.

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Styled in slate In this month’s instalment of our roofing matters series that shares insight

directly from experts across the roofing sector, we talk to Andrew Whitaker, founder and owner of Naturally Slate. An authority on slate roofing, his

answers to the below questions explain why slate is synonymous with style.

Closed boarding with conventional slate.

Photographs: Courtesy of Naturally Slate

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SA ROOFING: What are the different types of slate tiles and application methods?

WHITAKER: Essentially, there are three different types of slate used in South Africa:

Nutec Roof Slates from Everite Building Products (Pty) Ltd.: Nutec fibre cement slate, completely asbestos-free for well over a decade already, is widely used as a more affordable alternative to natural slate.

South African slate: Major suppliers of South African slate are Elephant Slate, HP Plum, and Mazista Tiles (Pty) Ltd. The slate is quarried from opencast mines in the Northern Province and Mpumalanga, and it primarily comes in various shades of grey, with some other colours also available.

Mazista was the first, and today remains the largest, supplier of South African slate, and it is not uncommon to hear the name Mazista used to refer to South African slate in general. Mazista slate, combined with the Peterlo® method, is the most popular natural slate system in South Africa.

Conventional: Conventional slating originated before the concept of underlay got introduced, and refers to the triple overlap method of laying the slate. Conventional slate is making a comeback in South Africa as a replacement for old asbestos slate and perished Welsh slate. Because it is a thinner option, it is easy to cut and shape – making it possible to produce roofs of exceptional complexity and beauty. Towers and curved roofs are possible using the conventional system.

The primary advantage of using conventional slate is that it does not require an underlay (Malthoid) in order to be waterproof. Because of the small overlap that results when using the Peterlo® system, there is a physical gap between slates that can only be made waterproof using an underlay. Malthoid has a shelf life of about 15 to 20 years, which means re-roofing an already expensive roof well before the slate itself shows any sign of deterioration. In addition to the Malthoid aspect, a conventional slate roof produces about half the load on the roof trusses (.35kN per kg for the conventional option compared to .75kN). This allows for a lighter truss design and savings on the cost of the trusses.

South African slate installed in Pearl Valley.

Spanish slate installed at Pearl Valley in Paarl.

A SLATE SNAPSHOT BY NATURALLY SLATE

• Slate is a low-grade metamorphic rock, made up of fine-grained silts and mud types.

• Slate is predominantly associated with sedimentary belts, but some slate is of igneous (volcanic) origin.

• Slate is commonly found in most countries.• Slate belts (abundant rock types) are often mined

commercially. Major areas include France, Spain, Wales, Brazil, China and also South Africa.

• Slate has been used in building for thousands of years.

• Slate’s simple extraction and workability into a useable product means it has a low carbon footprint.

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SA ROOFING: What maintenance is required for slate roofs?

WHITAKER: No roof type is maintenance free, and a slate roof needs to be serviced from time to time. If a broken slate tile exposes the Malthoid to the sun’s harmful UV rays, it will result in accelerated deterioration.

A broken slate on a conventional slate roof will also need to be changed, even though it is unlikely to result in a leak due to the triple overlap that conventional slate roofing provides for.

SA ROOFING: What about advances made in the industry, over time?

WHITAKER: The modern system of conventional slate roofing uses a stainless steel storm hook to hold the slate in place. This is particularly important in the windy coastal conditions around South Africa. Because the hook secures the slate from below, a broken slate can easily be changed by opening the head of the hook, sliding the broken slate out, and sliding a new slate into place. It is therefore fair to say that maintenance on a conventional slate roof has become much easier.

SA ROOFING: Do you need special trusses to accommodate the load of a slate roof?

WHITAKER: As mentioned, conventional slate roofs require slightly lighter trusses than those roofs slated with underlay. But generally, truss centres on a slate roof are 760mm between trusses. This is a specification dictated to the manufacturers and certified by MiTek, the recognized authority with respect to signing off the integrity of the roof structure.

SA ROOFING: How long will a slate roof last the homeowner?

WHITAKER: Because slate is a natural product and formed over millions of years under conditions of heat and weight, it

is an extremely strong and durable product. Imported slates from France, Spain and Brazil are geologically much harder than South African slate. The softer South African slate can be prone to flaking, but as a general rule of thumb, the slate itself will last for more than a generation.

SA ROOFING: What is the cost of putting on a slate roof?

WHITAKER: To be frank, slate roofs are not cheap, although they are less expensive than thatch, copper and pure zinc roofs. Tiled and sheeted roofs are at the lower end of the cost range, but generally speaking, a slate roof is about double the cost of a tiled or tin roof. Bear in mind though, that a slate roof will outlast a tin roof threefold, provided it is correctly maintained. I have seen slate roofs in Cape Town that are more than 100 years old but still in perfect condition. My own roof in France, where I worked for longer than 10 years, was well over 150 years old.

For more information, visit www.naturallyslate.co.za or send an email to the author at info@naturallyslate.co.za.

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South African slate with damp coarse.

Work in progress at Valkenberg Hospital.

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11 - 12 August 2016, Cape Town International Convention Centre

Conference Trade Expo∙

Conference Trade Expo∙

ConferenceTrade Expo

ConferenceTrade Expo

CLIMBING TO NEW HEIGHTS INTHE WESTERN CAPE’S CONSTRUCTION INDUSTRY

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• Meet professionals from the public and private sector from the entire construction value chain

• If you are a supplier or service provider and want to be a part of the Western Cape construction industry get in touch to sponsor/exhibit and expand your business network!

What to expect?

3500+ attendees

20+ hours dedicated networking

100+ exhibiting companies

40+ media and association partners

R1,5 million+ marketing coverage

Contact us todayand quote CCESAR02

to book your space

rashaad.essop@hypenica.com 021 700 4356

CapeConstruction Cape-Construction @CT_ConstructionJoin the conversation

The new system is set to be launched early this year, says Lea Smith, Past President of MBA North, and the driving force behind the new system. “Under the new

Construction Regulations, more stringent health and safety obligations have been placed on a wide range of parties involved in construction work, including the client, subcontractor, designer and principal contractor,” says Smith. “The Regulations clearly specify that all stakeholders must be involved in the implementation, maintenance, monitoring and enforcement of the Construction Regulations' legislative requirements, which include legal appointments, regular health and safety audits, medical certificates of fitness for all employees, and a Construction Work Permit or Construction Notification. All of these must be in place before any construction work can start."

At the 2015 Department of Labour Conference, the Department's Chief Inspector, Tibor Szana, appealed to the building sector to reverse the "intolerable loss of life" in the industry. The challenge was to step up inspection and enforcements, he stated then. With this in mind, MBA North developed the CHS-IT system.

“The system is a proactive online solution to help implement, monitor and enforce the Construction Regulations in real time, across multiple construction sites, conveniently from any smart device or personal computer,” says Smith. Included in

the system's benefits are: ease of use, time-saving, accessibility from any 'smart' device, real-time monitoring and reporting, recording of health and safety audit information, storage of health and safety documentation, automated audit reports, and monitoring of contractor compliance in real time.

The CHS-IT system also has an online automated Work Permit and Construction Notification submission, saving time and money. "It is a secure Cloud-based system, making accessibility to the information quick and easy. When Internet connectivity is poor or unavailable, information will be stored in the CHS-IT App and automatically uploaded when connectivity is restored. An added advantage of the system is that it is multi-user based, meaning that more than one safety officer can be working and engaging with the system at any one point in time," Smith adds. “One of the exciting elements of the CHS-IT system is its third-party external audit function that allows for 5% of all sites using the system to be up for possible selection for an audit on a month-to-month basis. The intention of the audits (by building industry-trained health and safety officers) would be to provide information and guidance based on the audit to the construction manager or client about the conformance of the site in terms of the Construction Regulations," concludes Smith.

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and safety I.T. system Master Builders Association North has developed a Construction Health and Safety Information Technological (CHS-IT) system aligned with the

requirements of the government's new Construction Regulations.

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9-11JUNE2016

Gallagher Convention Centre | Midrand | South Africainfo@woodexforafrica.com | +27 (0) 21 856 4334

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Many more Timber related products, machinery and services.

‘Working at Height’ means work in any place where, if there were no precautions in place, a person could fall a distance liable to cause personal injury or even death. This is not only in South Africa, but across the world – in both developing and advanced nations.

In 2015, the Institute for Work at Height Trade Association and Professional Body, together with many other organizations operating in the construction, mining, occupational health and safety environments, embarked on developing a ‘Guidelines for Safe Working at Height.’ Subject matter experts from all industries where people have to work at height were invited to participate in the development of these guidelines under the chairmanship of Dave Bass. The development of the guidelines was also discussed with the Department of Labour’s Chief Inspector, Tibor Szana, who nominated two persons from his office to also be involved in the process. The draft of the guideline document was shared with them on a continuous basis for their input. Other appropriate industry bodies were also consulted from time to time as the project developed. The purpose of the guidelines is to provide supervisory staff with the necessary basic knowledge to understand and ensure safety for tasks that are to be carried out at height. The input from several industries’ experts in their appropriate individual fields assisted in looking at ways of improving current practices and making work at height safer for everyone. The scope did not focus on any one particular industry, but rather at persons who, through the course of their work, are required to be in an elevated position and be exposed to a risk of falling.

As the Guidelines for Safe Working at Height were developed for industry by industry, it was decided to officially launch this document at a conference later this year (date and venue to be confirmed once available). The Chief Inspector, Tibor Szana, has indicated his willingness to be the keynote speaker at the event.

FOR MORE INFORMATION:

Institute for Work at HeightDr Alti Kriel, CEOTel: 011 450 1804 Email: pa@profbody.co.zaWebsite: www.profbody.co.za or www.ifwh.co.za

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TE ‘Guidelines for Safe

Working at Height’ coming this year

It is a common fact in the building, construction and maintenance industries that falling from height remains one of the biggest causes of fatalities and major injuries. Common cases include falls from scaffolding, ladders, and

through fragile surfaces. The Institute for Work at Height has worked with other key industry bodies to develop guidelines to mitigate the risk.

Information provided by: The Institute for Work at Height Trade Association and Professional Body

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