When the trussed rafter industry converges in a few weeks for its AGM near Leicester there will be a lot to reflect on, with both progress and change in the industry.
A sense of momentum was definitely in the air at the event a year ago, with a new PR strategy, a new installation guide for clients and plans for TRA/Structural Timber Association labelling of spandrel panels, to name but a few highlights.
Skills shortages and how to respond to highly prefabricated roofing systems were also some of the challenges aired. Now, going into 2018, a host of TRA initiatives and a new website are propelling the organisation forward as it seeks to engage better with the industry, customer sectors and help raise quality and safety standards.
One of the talking points at the AGM is likely to be the fallout from the Grenfell fire. “Post-Grenfell, the biggest threat and opportunity to our industry is the same – the position we take on the design and testing of fire safety solutions; and the materials we choose to use,” Jonathan Fellingham, TRA chairman, told TTJ.
“We can go for cheapest, put up with the inconsistencies in testing, and just follow the path of least resistance,” he added.
“The construction industry has a long culture of cheapening materials, so we can continue to work within that culture and face the longer-term consequences.
“Or we can decide to change that way of thinking and to work collaboratively within the TRA to agree genuinely robust solutions on fire safety. That’s what I would like us to do – agree a common spec based on quality materials and excellent design, get generic testing done which is meaningful, and build greater trust in our products for the greater good of the industry.
“Whether it’s a trussed rafter design, a metal-web joist detail or housebuilders’ use of spandrel and gable panels, there’s an opportunity to up the standards and snuff out the cheats.”
The AGM will include updates on the TRA’s proposed new quality scheme for spandrel panels, its work with the NHBC and others to update technical guidance on gable panels, and on the outlook for the trussed rafter market for 2018.
New website
One of the TRA’s main new ways of engaging the industry with its customers is an improved website – now live – providing technical support to homebuilders, architects and self-builders.
The new platform has simpler navigation, easy-to-download advice and guidance, news and events, and a dedicated career section.
“The new website has made it much easier for anyone interested in trussed rafters, spandrel panels or metal web joists to find what they need, whether they’re in the office or out and about,” added Mr Fellingham.
The technical advice and downloads section has been designed for easy use by designers, manufacturers and installers of roofing and flooring structures. Projects undertaken by members are on company profile pages to show trussed rafters being used in various types of buildings. Becoming a TRA member has also become more straightforward, with an easy online application form.
Ireland batten move
Changes to slating and tiling guidelines in Ireland highlights a substantial change for roof battens as they are now required to be strength graded.
On January 1 this year, the Standard Recommendation 82:2017 slating and tiling code of practice (SR 82) formally replaced Irish Code of Practice 2:2002 slating and tiling.
The TRA in Ireland is notifying members that a comprehensive quality check will no longer suffice for roof battens, while another change in the new guidance includes the requirement for SR 82 to be specified on all relevant drawings.
“Currently, standards don’t adequately deal with visual grading for small timber sections,” said Alan Armstrong, TRA Ireland chairman.
“But we’ve been advised that machine graded and CE Marked roof battens are already out there, in a variety of sizes, which meet the European Standard EN 14081 and provide buyers and certifiers with evidence of compliance.”
Spandrel panel guidance
Important new roofing guidance aimed at masonry-built homes, published by the TRA (and endorsed by the NHBC) towards the back end of 2017 was designed to reduce the risks, costs and waste from poor spandrel panel construction by housebuilders.
It was devised after trussed roof manufacturers reported increasing interest in offsite prefabricated spandrel components, especially from large and volume housebuilders building low-rise housing and apartments.
In a recent NHBC survey of 8,000 new homes sites, about 17% were already using spandrel panels.
The guide – developed with the NHBC and Structural Timber Association – provides evidence-based technical best practice on the design, structural requirements, fire and acoustic performance, weather protection and safe installation of spandrel panels.
It will receive further updates following the outcome of further fire testing, with more details of the TRA’s proposed new quality scheme for spandrel panels to be shared soon.
“As the use of pre-manufactured components and offsite construction grows in popularity, housebuilders are increasingly turning to spandrel panels,” said Mr Fellingham.
Last year, the TRA presented at the NHBC Building for Tomorrow roadshows, speaking to more than 700 housebuilders, addressing issues and providing guidance on spandrel panels.
BIM Status
The TRA was also granted ‘Relevant Authority’ status by the Construction Products Association (CPA) last autumn to ensure trussed rafters and metal-web joists were consistently represented in Building Information Modelling (BIM) models, regardless of the design software in which they originate.
This means the TRA is the recognised authority for specifying the data that is relevant for its members’ products.
Industry software suppliers have agreed the consistent data set for trussed rafters and metal-web joists and the CPA LEXiCON tool being developed will be the method used to deliver the product data in an industry common language.
TRA members modelling engineered 3D timber products using advanced software systems is not a new thing.
However, the challenge has been to establish a consistent way for its members to collaborate with the construction sector across a range of different software platforms.
Safe Installation guide
Another new TRA guide is the result of a partnership with health and safety consultants Paramount Safety Solutions.
‘How to safely install roof trusses’ for new homes of masonry construction has been published to help reduce risks on site to builders working at height.
Despite an overall reduction in fatalities, working at height remains the biggest danger for construction workers and installing roof trusses is a complex and potentially risky job for housebuilders. The guide gives information needed on preparing and installing roof trusses safely, and will provide principle designers and main contractors with a basis for their CDM construction phase plan.
“With the dangerous combination of a strong drive to build more new homes faster than ever before and a significant skills shortage in the sector, we have real concerns about whether contractors are receiving the right training and guidance when it comes to working on the roof,” said Mr Fellingham.
“Due to how unstable roof trusses are in the first stages of installation, a full site specific risk assessment must be undertaken by either the contractor or installer,” added Jake Tyrell, health and safety director at Paramount Safety Solutions.