The RTA and most organisations, including the NHBC, require that roof slates and tiles are fixed in accordance with BS 5534:2014+A2:2018. ‘Slating and tiling for pitched roofs and vertical cladding’, the current code of practice for calculating fixing specifications for roof slates and tiles in the UK.
Roof tile fixing specifications that comply with BS 5534: 2014+A2: 2018 comply with the design wind load requirements of BS EN 1991-1-4:2005 + A1:2010, Eurocode 1 – Actions on structures, Part 1-4: General actions – Wind actions, and NA to BS EN 1991-1-4:2005 + A1:2010, UK National Annex to Eurocode 1 – Actions on structures, Part 1-4: General actions – Wind actions, as well as minimum tile security requirements set out in BS 5534: 2014+A2: 2018.
Wind uplift and fixing specification calculations are complex, taking into account a multitude of location and building factors, including but not limited to; distance from the sea, altitude above sea level, terrain and orography, building dimensions and roof pitch. As all Manufacturers’ fixing requirements are individual to their products and vary in performance, it is vital to obtain the manufacturer’s fixing specification for each site and furthermore, each building/plot type, to ensure that a suitable fixing specification is adopted. A fixing specification is usually a requirement for organisations like the NHBC to comply with their Technical Standards and their 10-year Buildmark Warranty. The manufacturer’s specified fixings, appropriate for the tile type, should always be used to ensure the roof is fixed correctly.
In conclusion always contact the manufacturer of the tiles you are using for the correct fixing specification and fixings to be used.