BS 5534

BS 5534, Slating and tiling for pitched roofs and vertical cladding – Code of practice, is published by BSI and is the main UK standard for the design and installation of slate and tile roofs. It covers materials, underlays, battens, fixings, weathertightness and resistance to wind. The current version is BS 5534:2014+A2:2018.

The 2014 revision and later changes

The 2014 edition, which came fully into effect in 2015, made several significant changes:

• No mortar-only fixing. Mortar can no longer be relied on as the only means of securing roof tiles. Ridge and hip tiles, and single-lap tiles, must be mechanically fixed even where mortar is used for bedding.
• Perimeter tiles. Tiles at the edges of the roof (eaves, verges, ridge, hips) are to be fixed twice, because wind suction is highest there.
• Higher wind loads. Revised wind calculation, aligned with Eurocode wind loading, generally means more fixings than older practice.
• Underlays. Underlays must be classified for wind uplift resistance using prescribed tests, with a maximum drape between rafters of 15 mm (0.6 in). Definitions of low-resistance (LR) and air-permeable underlays changed.
• Scope. Re-roofing and repairs were brought within scope, with a note that heritage roofs may need a different approach agreed with planning authorities.

The 2018 amendment (A2) refers to BS 8612, which sets requirements for dry-fixed ridge, hip and verge systems, including their fixing and ventilation.

How fixing is decided

BS 5534 uses wind loads from EN 1991-1-4 and its UK National Annex, combined with uplift resistance data for the tile and fixing (often from EN 14437 tests), to determine fixing requirements for each part of the roof. Manufacturers publish fixing specifications based on site location, altitude, roof pitch and building height.

Workmanship

On-site workmanship is covered by the companion standard BS 8000-6. Warranty providers in the UK new-homes market, such as LABC Warranty, refer to BS 5534 compliance in their technical standards.

Influence

Although written for the UK, BS 5534 is used as a reference in Ireland and in other countries that follow British roofing practice.