In its current guise, the code of practice for slating and tiling, BS 5534:2014, has been mandatory since February 2015. A first amendment was issued later the same year.
February 2018 saw the publication of an updated version with a second amendment. A transitional period for its introduction ends in July 2018. It is likely to become formalised in NHBC technical standards at the beginning of 2019.
BS 5534:2014 + A2:2018 aims to further improve the security, durability and weather-tightness of new and refurbished pitched roofs. It does this in part by referring to a brand new British Standard, BS 8612:2018, which sets out standards for dry fix roofing products and systems, in response to issues of product quality and installation issues.
The full document can be purchased from the BSI website.
As a code of practice, the standard sets out guidance and makes recommendations on best practice for the installation of a roof. Installing to the British Standard isn’t required by law, but its inclusion in a specification can be upheld in court if necessary and following its guidance aids compliance with building regulations.
Its contents include batten selection, methods of fixing, wind uplift formulas, and a means of calculating fixing specifications. Product manufacturers in the roofing industry typically make sure their installation guides are aligned with BS 5534, with any deviation requiring documented evidence to prove suitability.
Third party warranty providers like the NHBC or Zurich expect an installation to comply, and the standard is also a foundation for competency schemes like Competent Roofer.
The initial overhaul of BS 5534 was driven by extreme weather putting greater strain on roofs and increasing insurance claims, and the need to align with European Standards and equivalent Eurocodes.
Mortar could no longer be relied upon as the only means of securing the roof covering. Single lap roof tiles, and hip and ridge tiles, all had to be mechanically fixed regardless of the use of mortar; tiles to the perimeter of a roof had to be fixed twice. Higher wind loads were assumed, requiring more fixings generally and improved guidelines on the installation of underlays.
The revised BS 5534 changed the roofing market and significantly increased the use of dry fix roofing systems. The 2018 amendment addresses the challenges that resulted, setting minimum standards for dry fix products and improving the quality of pitched roof installation.
Among the most significant changes are:
More onerous fixing specifications increase installation times, especially where clipping is required. All roofs laid in single lap tiles require some clipping, traditionally using either two-piece aluminium or stainless steel clips and nails.
Marley’s SoloFix one-piece clip and nail provides an affordable fixing for all standard interlocking tiles. It is up to 30% faster to install than traditional clips, and delivers outstanding strength and durability.
The widespread adoption of dry fix roofing systems will continue, but is not a new solution. Marley have produced dry fix products for 30 years and continue to offer an extensive range. Our ridge and hip systems are mortar and maintenance free, and are capable of providing sufficient ventilation to meet the requirements of BS 5250 (code of practice for the control of condensation).
Where mortar bedding is necessary, we offer security ridge and hip kits with enough mechanical fixings to secure up to six metres of each. Clips for small tile cuts at the hip and valley are also available.