The full SPRA Design Guide 2016 is available to download. This Guide hyperlinks to all other SPRA Guides and Quality Standards, together with many vital industry references. Over twenty-five years, the Guide has reflected the transition from prescription and standard ‘solutions’ to a more performance-based construction process based on harmonised European Standards. Judging from the feedback SPRA gets, it’s very highly respected amongst our customers out there. The next revision of the Guide will be in Jan 2018. So what’s new?
Revised guidance and Toolbox Talk now available to download.
Recognition of Factory Mutual Data Sheet 1-29 (January 2016 version): ‘Roof deck securement and above-deck roof components’ and 1-49 ‘Perimeter flashing’.
There is extended advice on design for effective drainage, including options for creating falls in different types of deck. SPRA fully supports the requirements of BS6229 in respect of a minimum finished fall of 1:80 at any point in all roof systems and recognises the potential risks to thermal performance of allowing back-falls on inverted roofs.
The need to attenuate potentially high loadings on urban storm-water systems has been recognised for a decade. The Guide recognises the advantages of green roofing as a natural attenuator and of roof or ground-level storage as an option, but notes that any design which deliberately stores a head of water on the waterproof membrane requires a completely different approach. Like other manufactured membranes for roofing, certification does not extend to situations of hydrostatic pressure and is not within the scope of BS6229.
There is new advice on loading of roof systems by pedestrian finishes. The use of timber decking has increased dramatically, partly driven by the London apartment boom but also by fashion. There are rewards and risks, not least durability and access to rainwater outlets, all of which will be covered in a new guide to be developed in consultation with the Timber Decking and Cladding Association.
Although there is no sign of the draft for the 2016 revision of Approved Document Part L, the Guide includes a new section on the 2013 AD, with improved detail.
For further information please contact Jim Hooker, Technical Director at SPRA by emailing firstname.lastname@example.org