Notice of correction to Approved Document B 2019 edition

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To:

The Chief Executive:

Unitary, Metropolitan, District and London Borough Councils in England

County and County Borough Councils in Wales

The Town Clerk, City of London

The Clerk, Council of the Isles of Scilly

The Sub-Treasurer, Inner Temple

The Under Treasurer, Middle Temple

The Head of Building Control:

Unitary, Metropolitan, District and London Borough Councils in England

County and County Borough Councils in Wales

City of London

Council of the Isles of Scilly

Approved Inspectors cc: The Chief Executive:

County Councils in England

National Park Authorities in England & Wales

Chair: National Fire Chiefs Council

19September 2019

Dear Sir or Madam Notice of correction to Approved Document B 2019 edition

You will be aware that the department published a clarified 2019 edition of Approved Document B on 5 July 2019 which came into force on 30 August 2019.

I am writing to give notice under section 6 of the Building Act 1984 of some revisions to the above edition which are to correct errors. The Secretary of State withdraws approval of the sections of incorrect text set out below and approves the revised text also set out below. The new revised version of the 2019 edition of Approved Document B incorporating these changes is now available from the .GOV.UK website:

https://www.gov.uk/government/publications/fire-safety-approved-document-b

We expect it to be available from the publisher in hard copy shortly. Ministry of Housing, Communities and Local Government Fry Building 2 Marsham Street London SW1P 4DF Tel: 0303 444 0000 Email: enquiries.br@communities.gov.uk www.gov.uk/mhclg

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The revisions set out below take effect from the date of this letter and I would be grateful if you would notify your members of these changes.

The approved revisions set out below relate to the requirements in Part B, Schedule 1 Regulations 6(3), 7(2) & 38 of the Building Regulations 2010.

Further information

The department has become aware of an error in the guidance relating to dampers fitted to smoke shafts in blocks of flats. The error related to the incorrect use of the defined term “fire and smoke dampers” in paragraph 3.51 iii of volume 1 (Dwellings).

On further review, a number of other typographical errors have been identified and corrected as set out below.

Notice of revisions to the 2019 edition of Approved Document B (‘ADB 2019’):

•1- Smoke control dampers:

The operation of a “fire and smoke damper” conforming to BS EN 15650 would not meet the operational requirements for venting via a smoke shaft. Therefore the wording has been revised to refer to “smoke control damper” instead.

The following text in ADB 2019 volume 1 paragraph 3.51 iii. is withdrawn and no longer approved:

Withdrawn text:

“The smoke shaft should be constructed from a class A1 material. All vents should either be a fire doorset (see Appendix C, Table C1, item 2.e for minimum fire resistance) or fitted with a fire and smoke damper (see paragraph 9.21). The shaft should be vertical from base to head, with a maximum of 4m at a maximum inclined angle of 30 degrees.”

The above text shall be replaced by the approved text below:

New approved text:

“The smoke shaft should be constructed from a class A1 material. All vents should either be a fire doorset (see Appendix C, Table C1, item 2.e for minimum fire resistance) or fitted with a smoke control damper achieving the same period of fire resistance and designed to operate as described below. The shaft should be vertical from base to head, with a maximum of 4m at a maximum inclined angle of 30 degrees.”

•2- Double-skinned insulated roof sheeting:

Diagram 5.2a (volume 1) diagram 8.2a (volume 2) with the associated text in paragraph 5.14 (volume 1) and 8.28 (volume 2) is corrected to remove the text “with a thermoplastic core”.

The following text in ADB 2019 paragraph 5.14 in volume 1, and paragraph 8.28 in volume 2 is withdrawn and no longer approved:

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Withdrawn text:

“Double-skinned insulated roof sheeting with a thermoplastic core should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.”

The above text shall be replaced by the approved text below:

New approved text:

“Double-skinned insulated roof sheeting should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.”

The following text in ADB 2019 diagram 5.2a in volume 1, and in diagram 8.2a in volume 2 is withdrawn and no longer approved:

Withdrawn text:

“Double-skinned insulated roof sheeting with a thermoplastic core should incorporate a band of material of class A2-s3, d2 or better at least 300mm wide centred over the wall.”

The above text shall be replaced by the approved text below:

New approved text:

“Double-skinned insulated roof sheeting should incorporate a band of material of class A2- s3, d2 or better at least 300mm wide centred over the wall.”

The corrections in relation to double-skinned insulated roof ensures there is no technical change between the revised 2019 clarified Approved Document B and the 2006 edition.

•3- Fire detection and alarm systems in large dwellinghouses:

ADB 2006 (including amendments) referenced BS 5839:2004 which included a minimum of “Grade B” fire detection and alarm system. BS 5839:2019 no longer defines Grade B, as such the wording in ADB 2019 Volume 1 has been revised.

The following text in ADB 2019 paragraph 1.6 in volume 1 is withdrawn and no longer approved:

Withdrawn text:

“A large dwellinghouse of two storeys (excluding basement storeys) should be fitted with a Grade B Category LD3 fire detection and alarm system, as described in BS 5839-6.”

The above text shall be replaced by the approved text below:

New approved text:

“A large dwellinghouse of two storeys (excluding basement storeys) should be fitted with a Grade A Category LD3 fire detection and alarm system, as described in BS 5839-6.”

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•4- Reference to BS 5839-6:

The reference to BS 5839-6 in Appendix F needs to be updated to the correct date.

The following text in ADB 2019 volume 1 and volume 2 Appendix F is withdrawn and no longer approved:

Withdrawn text:

“BS 5839-6 Code of practice for the design, installation, commissioning and maintenance of fire detection and fire alarm systems in domestic premises [2018]”

New approved text:

“BS 5839-6 Code of practice for the design, installation, commissioning and maintenance of fire detection and fire alarm systems in domestic premises [2019]”

•5- Doors on escape routes:

A typographical error is addressed by correcting “opened” with “openable” in ADB volumes 1 and 2.

The following text in ADB 2019 paragraph 3.90 in volume 1 is withdrawn and no longer approved:

Withdrawn text:

“Doors should be readily opened to avoid undue delay to people escaping. Doors on escape routes (both within and from the building) should comply with paragraphs 3.91 to 3.98. Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.

NOTE: Paragraphs 3.91 to 3.98 do not apply to flat entrance doors.”

New approved text:

“Doors should be readily openable to avoid undue delay to people escaping. Doors on escape routes (both within and from the building) should comply with paragraphs 3.91 to 3.98. Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.

NOTE: Paragraphs 3.91 to 3.98 do not apply to flat entrance doors.”

The following text in ADB 2019 paragraph 5.6 in volume 2 is withdrawn and no longer approved:

Withdrawn text:

“Doors should be readily opened to avoid undue delay to people escaping. Doors on escape routes (both within and from the building) should comply with paragraphs 5.7 to 5.15. Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.”

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New approved text:

“Doors should be readily openable to avoid undue delay to people escaping. Doors on escape routes (both within and from the building) should comply with paragraphs 5.7 to 5.15. Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.”

Please can you distribute amongst your members to ensure they are aware of this update and are using the most up to date version of Approved Document B. Enquiries

Telephone enquiries on this Circular Letter should be addressed to Technical Policy Division on 0303 444 0000 and all e-mail enquiries to enquiries.br@communities.gov.uk

Yours faithfully

F Kirwan

Deputy Director

Technical Policy Division, Building Safety Portfolio