Following Government consultation major changes to Approved Document B are due in December 2022, including balcony flooring with only A2fl-s1 rating becoming exempt from A2-s1, d0 requirement, although caveats apply
With the Government recently issuing its response to the consultation on the ban on combustible materials in and on the external walls of buildings, major changes are on the horizon. Approved Document B especially is set for a series of major amendments, one of which regards a new exemption from the requirements for materials to hold A2-s1, d0 fire ratings, a certificate earned by performing suitably in a “walls and ceilings” vertically-oriented fire test.
Currently, all materials in balcony construction on buildings over 18m must be fire rated A2-s1, d0. Some decking manufacturers have only submitted their products to flooring-specific fire testing, though, so only hold A2fl-s1 certification, meaning that they are not compliant with the requirement. Government will now amend Approved Document B to allow the use of balcony flooring that only holds the flooring test’s A2fl-s1certificate, as the testing process is similarly rigorous to the alternative walls and ceilings test.
There is an important caveat within the amendment text, though. It states that material that “forms the top horizontal floor layer of a balcony” and achieves class A1fl or A2fl-s1 is exempted, but only if “the entire layer has an imperforate substrate under it”.
This means that the exemption only applies to balconies that have a solid, imperforate layer beneath the decking such as soffit cladding. This is because the flooring-specific fire test does not test for flaming droplets whereas the walls and ceiling test does.
So, decking boards that only have this flooring fire rating are not proven to not produce flaming droplets that could ignite fires beneath the balcony and aid in the spread of fire.
This represents a major change in Approved Document B and it sounds like a pragmatic step in the right direction. The caveat for an imperforate layer, though, is subtle in the document and may catch out any building designers, architects or specifiers that miss it, leading to possible further costs in putting the mistake right.
The amendment comes into force on 1st December 2022. After this date, new buildings that have projecting balconies will be affected and will need to be compliant. If a soffit or other imperforate layer is not designed into the balconies then the use of A2fl-s1 balcony decking boards would be non-compliant.
AliDeck aluminium decking boards have been subjected to both forms of fire testing and achieve A2-s1, d0 and A2fl-s1 fire ratings. This provides our customers with total peace-of-mind that when using AliDeck boards they are fully compliant with the Building Regulations and all aspects of Approved Document B.
To find out more about AliDeck and achieving total compliance, please call the team on 01622 235 672 or email info@alideck.co.uk.
