There have been further changes to fire safety requirements in the Building Regulations and the use of non-combustible materials in and on the external walls of new flats, hospitals, student, school accommodation and dormitory buildings (originally introduced in 2018).

The announced changes take into account responses to the consultation process in 2020 and extend the scope of the requirements for non-combustible materials to cover hotels, hostels and boarding houses.  Other updates to the regulations include the following recommendations:

  • include elements of solar shading devices within the scope of the ban
  • amend the list of materials exempt from the ban to include fibre optic cables and insulation materials 300mm from ground level
  • update the requirement of the ban to refer to the latest version of the British Standard classification for materials used on high-rise residential buildings
  • temporarily exempt cavity trays
  • amend the requirements for material change of use in buildings

The cavity tray exemption is significant in the SFS sector as the exemption previously applied to:

(a) cavity trays when used between two leaves of masonry;

Whilst this statement remains unamended in the Approved Documents the changes announced in June 2022 include the following recommendation:

Exemptions – The legislation will amend the list of materials exempted from the combustible materials ban to include fibre optic cables and insulation up to 300mm from ground level. We will also provide an 18-month temporary relaxation for cavity trays in all forms of construction.

To support this Government has issued a dispensation notice that allows use of cavity trays that do not achieve the strict performance requirements of the ban – this exemption therefore comes into effect from the 1st June 2022.  FIS continues to work with officials and colleagues at the Construction Products Association to try to understand the rationale behind the temporary relaxation and what this means longer term.

The announcement also carries a number of recommended changes including allowing for new statutory guidance to restrict the combustibility of materials used in and on the external walls of residential buildings, between 11-18m in height.  This will mean that lower risk developments between 11-18m “must meet necessary safety standards – while allowing designers and developers flexibility to use environmentally friendly materials.”  Further consultation is anticipated on this aspect in the coming months.

A complete ban is to be introduced on the use of metal composite material with un-modified polyethylene core in all buildings of any height.

Unless specified, changes to the Building Regulations will come into force on 1 December 2022 (in line with the full publication of the revised Approved Document B).

We will continue to keep you updated, but if you have any comments you would like to feed in at this stage to our ongoing discussions with officials at DCHLUC, please don’t hesitate to play them in via

Full details available here.

Note this move will (for the period of the exemption) align more closely with the Scottish Building Standards that were extended on the 1 June to cover Buildings 11-18m.  These also exempt Cavity Trays from the combustible material list:  Changing legislation in Scotland – FIS (

This announcement coincides with the publication of a booklet containing ammendments to Approved Document B that will come into force from the 1st December 2022.

Cavity Tray Exemption – Further Details

Extract from the consultation response related to the Temporary Exemption of Cavity Trays:

In our consultation we proposed several changes to the list of exemptions in Regulation 7(3) including the temporary exemption of cavity trays in all forms of construction and the extension of the exemption of waterproofing and insulation materials.

Cavity trays are an essential wall component, installed in wall cavities to capture moisture that penetrates the outer face of the wall, preventing damp. Cavity trays are currently exempt only when used between walls constructed of two leaves of masonry. This type of construction is not common in modern high-rise buildings and industry has adapted by using stainless steel to produce cavity trays. However, industry has highlighted that this incurs excessive cost and there are issues with supply, installation and durability. Stainless steel is considered less durable than a plastic cavity tray and does not effectively prevent damp. There is increased potential for health and safety issues to arise if these products fail to adequately prevent moisture ingress and damp in buildings.

We are aware of some compliant non-combustible product on the market, however some industry stakeholders have expressed concerns over the installation of this product that may result in poor performance and issues of damp in buildings. We are aware that some developers have been unable to get a new homes warranty, making the homes unsaleable, due to concerns over the performance of non-combustible cavity trays.

The consultation proposed a temporary 18-month relaxation of the ban as it relates to cavity trays pursuant to Section 11 of the Building Act 1984. This would enable this matter to be resolved temporarily while maintaining industry momentum to develop adequate non-combustible alternatives. 68% of consultation respondents agreed with the proposal.

In the interest of health and safety, we will issue a type relaxation to allow industry to use cavity trays that do not achieve the strict performance requirements of the ban. We do not believe it is appropriate to permanently exempt cavity trays as it would hinder innovation in development of additional compliant products. It remains the clear intention of this government to ensure that non-combustible cavity trays are used in the external walls of building where they are already readily available and after the temporary exemption lapses.