Amended Building Regulations released
The changes focus on the ban in the use of combustible materials in and on external walls of buildings, which includes balconies, this particularly affects the use of polymer materials, including interlayers in laminated glass balcony panels, and composite panels with a polymer core.
In changes to the Building regulations, notice has been given of the Building etc. (Amendment) (England) Regulations 2022 (S.I. 2022/ 603) (the “Regulations”) and publication of Approved Document B 2019 edition incorporating 2020 and 2022 amendments.
Both the Regulations and Approved Document B guidance will come into effect on the 1 December 2022.
Perhaps the most contentious change comes in changes to balconies, the changes mean laminated glass can no longer be used on balcony panels where the building has a storey above 11m. This is due to the polymer interlayer being combustible and not included in the list of exceptions.
A new definition of reaction to fire classification is given, which updates the classification. Building works within the scope of the current restrictions on combustible materials will have to meet this updated reaction to fire classification, under BS EN 13501-1:2018. It also inserts a new definition of relevant metal composite material.
A ban is introduced on relevant metal composite material becoming part of the external wall or specified attachment. Relevant metal composite material is:
Any panel or sheet, having a thickness of no more than 10mm, which is comprised of layers:
(i) two or more of which are made of metal, alloy or metal compound; and
(ii) one or more of which is substantial and is made of a material having a gross calorific value of more than 35 MJ/kg when tested in accordance with BS EN ISO 1716:2018.
Other changes to the regulations include provision of secure information boxes and evacuation alert systems for buildings over a set height, both will assist fire and rescue services if needed.
The Secretary of State has made a direction for the temporary relaxation of regulations 6(3) and 7(2) of the Building Regulations 2010 in relation to cavity trays (cavity barriers in external walls). These are already exempt from the requirements of the ban when used between two leaves of masonry. However, modern high-rise buildings often use different construction types. Therefore, the regulations bring forward a relaxation which exempts cavity trays from the performance requirements of regulations 7(2) and 6(3).
The relaxation comes after some parts of industry were found to be opting for sheet metal shaped on site. This practice raised questions about the durability of these materials with long-term exposure to water and the potential for structural damage over time.
The relaxation is for 18 months to allow manufacturers to establish a clear supply chain for non-combustible cavity trays.