Combustible Materials Ban in High Rise Residential Buildings

21st Dec 2018

Amendments to the Building Regulations made on the 28 November 2018 and coming into force on 21 December 2018 will see a ban of COMBUSTIBLE MATERIALS in certain “relevant” high rise residential buildings. These changes are in the main a response to the government consultation on the ban of the use of combustible materials in cladding systems on high-rise residential buildings following the Grenfell Tower Fire on the 14 June 2017.

Please note for now these changes apply only to buildings and building work in England. We will keep you updated with further amendments applicable to building work in Wales.

Technical Update

It is important to understand that the ban of combustible materials in respect to compliance extends to residential buildings with a floor over 18m (not including any storey consisting exclusively of plant) and falls under the definition of a “Relevant Building” as follows:

• contains one or more dwellings
• contains an institution. These will be your hospitals, homes, schools or similar establishment used as living accommodation for treatment, care etc
• contains a room for residential purposes including student accommodation, care homes, sheltered housing, dormitories in schools, BUT excludes hotels, hostels and boarding houses

The above definitions, although not explicitly stated in the changes, generally relate to buildings where a stay put or a managed phased evacuation strategy is to be implemented. Please note by implementing a simultaneous evacuation policy the ban of combustible materials on the above buildings will still be required.

Stroma Building Control has a duty of care and responsibility to provide you with the best counsel in particular in relation to fire safety matters. Therefore it follows that we would recommend that consideration is given to the limitations of external wall materials where a stay put or phased evacuation policy is provided to any building including buildings under 18m.

In practice to the above requirements, materials used on relevant buildings described above will be limited to the following European Classifications, classified in accordance with BS EN 13501-1:

• Class A1. Products described as having no contribution to fire at any stage
• Class A2-s1,d0 products described as having no significant contribution to fire at any stage.

There are a number components within the construction of the wall that maybe excluded from this requirement given in Regulation 7(3). Notable exclusions are as follows:

• seals, gaskets, fixings, sealants and backer rods
• nembranes. However they should achieve a minimum euro classification B-s3,d0
• insulation and waterproofing material below ground
• doors, windows and their frames and glass
• intumescent and fire stopping materials There remains the option to use a wall system that has been tested to BS 8414 and classified to BRE Report BR 135 Fire performance for buildings over 18m not described as a Relevant Building.

New definition of an external wall and specified attachments

• anything located within any space forming part of the wall;
• any decoration or other finish applied to any external (but not internal) surface forming part of the wall;
• any windows and doors in the wall; and
• any part of a roof pitched at an angle of more than 70 degrees to the horizontal if that part of the roof adjoins a space within the building to which persons have access, but not access only for the purpose of carrying out repairs or maintenance;

Specified attachments include balconies, solar panels and brise soleil.

Amendments to regulations 5 and 6 concerning a Material Change of Use

Significantly where there is a change of use to a relevant building as described above, the construction of the external walls and specified attachments must be investigated and where necessary work must be carried out to ensure they only contain materials achieving the European class A2-s1,d0 or class A1, other than those components exempted. Apart from the cost of these changes there is the real possibility that the thermal performance of the fabric of the building will be reduced by replacing an insulation board with a non combustible material that does not have similar thermal insulation properties, the replacement of thermal elements dependant on the extent could also be considered as a thermal renovation and have additional requirements in regards to the overall thermal performance of the element being renovated, which would also have a cost implication.

The drive to ensure relevant buildings only contain materials achieving the European class A2-s1,d0 or class A1, other than those components exempted is further highlighted by that Regulation 7(2) relating to relevant buildings that is your buildings over 18m and are either a dwelling, institution, or a room for residential purposes as discussed above will prevail over the provisions for external wall surfaces described in diagram 40 of approved document B.

The announcement and changes coming into effect have happened very quickly and the government have allowed a short transition period.

Transitional Arrangement

The Amendment Regulations come into force on 21 December 2018. However the Amendment Regulations will not apply where a building notice or an initial notice has been given to, or full plans deposited with, a local authority before 21 December 2018 and either the building work to which it relates:

• has started before that day; or
• is started within the period of two months beginning on that day.

There is a lot to consider in a very short period of time. We are here to help you understand the changes and give you the surety of compliance. Please do not hesitate to call or email your contact at Stroma Building Control for any existing projects or future developments.

Thank you,

Martin Watton, Technical Director