Building regulations approved document B

Do  my timber claddings or ceilings need fire treatment ? What level of reaction to fire classification or class is required?

In England and Wales, the fire requirements are covered by Approved Document Part B of the Building regulations: LABC Building Regulations Approved Document B Fire Safety

Building Regulations are intended to ensure that a reasonable standard of life safety is provided in case of fire. The appropriate use of timber products can play a critical part in improving the performance of buildings in fire and in extending the time available to occupants to exit the building.

What (Level) Class of fire treatment  should I specify for my timber cladding ? Andrew Goto
flame fire image

Approved Document B in Building Regulations covers fire safety in dwellings. It states that ‘The external walls of the building shall adequately resist the spread of fire over the walls and from one building to another, having regards to the height and position of the building.’

In many domestic situations, timber cladding can be used without the need for fire treatment. The requirement for treatment with a flame retardant depends on building height, boundary distances and the size of the cladding area being considered.

Approved Document B makes a clear distinction between the requirements for buildings with boundaries less than 1000mm and those with boundaries greater than 1000mm and provides guidance on what are acceptable unprotected areas within each category. For UK buildings over 18m tall, timber cladding must achieve a Euroclass B-s2, d2 standard. Therefore, it must be protected by an appropriately tested and certificated flame retardant product.

There are stringent testing requirements under European Standards for such products. An application of the fire treatment under quality assured factory controlled conditions is essential. Unless the timber cladding is to have a suitable, maintained coating, the flame retardant must be leach resistant and suitable for exterior use.Timber Cladding Fire Treatment Questions and Answers (FAQ)

© 2018 Andrew Goto All Rights Reserved | Terms & Conditions| Privacy Policy