Updates to the Building Regulations Approved Document B come into force from December 2022. This update clarifies several aspects of fire safety regulations affecting ‘residential’ buildings, including the use of materials and controlling the spread of flame through external wall surfaces.
We believe the regulations could have gone further and perhaps considered the fire safety performance of building systems alongside individual materials.
There’s a strong evidence-based case for allowing structural timber to be used extensively in a wider range of buildings – including residential buildings over 18m – particularly when timber elements are encapsulated in non combustible materials, as in i-FAST panels.
The updated guidance remains restrictive compared to regulations in force in other countries. But it does at least offer clarity for clients and developers looking to apply panelised offsite solutions to simplify the construction process and improve building performance.
The restrictions on the use of combustible materials only apply to buildings where people reside overnight.
Combustibility
The minimum combustibility of cladding materials is Class B for residential buildings up to 11m high and A2 for those between 11m and 18m high. Insulation in external walls for buildings between 11m and 18m high must now be A1 or A2. Effectively this means that all rigid foams (EPS, PIR,PUR) are banned above 11m.
The i-FAST system uses a stone fibre insulating layer. As this is a non-combustible material it means the panels are fully approved for residential buildings up to 18m high.
The system, which uses a rigid foam insulating layer sandwiched between OSB facing boards, is approved for use on buildings up to 11m high. The panels offer a major advantage for projects that want to maximise the amount of structural timber to reduce embodied carbon emissions.
It’s worth reiterating the fire related safety data for i-FAST panels. The timber framing used in the panels is enclosed in non-combustible fibre cement board and stone wool insulation. The panels have a surface spread of flame rating Class 0.
If you’d like to know more about how Innovaré panelised building systems can transform project outcomes contact enquiries@innovaresystems.co.uk or take a look at our resource centre.
