Warranty Position Regulatory Position and Guidance Exemptions Does B4 still apply?
Green indicates we consider our position best practice and not in dispute Grey items cover the December 2018 Amendments, Approved Documents and MHCLG's own FAQs and advice notes Green indicates that the item IS exempt from Regulation 7(2), in accordance with Regulation 7(3) Green indicates that B4 still applies, and refers to relevant parts
Yellow indicates our position has the potential to be subjective   Red indicates that the item is NOT exempt. Refer to Regulation 7(3) Red shows that B4 no longer applies


Warranty Position

Explanation/Notes: Buildings that are being redeveloped to include a flat/care home/hospital or undergoing another material change of use.

An existing building which already contains a dwelling, institution or a room for residential purposes (excluding any room in a hostel, hotel or boarding house) and which is undergoing a material change of use other than that described in regulation 5(k) (e.g. providing a greater or lesser number of dwellings than it did previously) must comply with the requirements of regulation 6(1) and regulation 6(2). The building works would also need to comply with regulation 7.

Requirement: All materials within the external wall are required to have a combustibility class A2-s1, or better, unless they are exempt within 7(3).

Is the position indisputable? Yes.

December 2018 Amendment

Reference: 6(3).

Reference titles: Subject to paragraph (4), where there is a material change of use described in regulation 5(k), such work, if any, shall be carried out as is necessary to ensure that any external wall, or specified attachment, of the building only contains materials of European Classification A2-s1, d0 or A1.

Approved Document

Reference: 10.13

Reference titles: Where the use of a building is changed such that the building becomes a building described in regulation 7(4), 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 class A2-s1, d0 or class A1, other than those exempted by regulation 7(3).

MHCLG FAQS / Advice Notes

Reference: Section 2

Reference title(s): Requires that the external walls and specified attachments must only contain materials which achieve European class A2-s1, d0 or class A1. This means that materials which do not achieve that minimum standard will have to be removed or replaced as part of the building work.


Is the item exempt from Regulation 7(2), in accordance with Regulation 7(3)?: No.

References: None.

Statement: None.

If exempt, are there any restrictions on the use of the system, component or material given in the guidance in ADB vol 2? None.

Does B4 still apply?

Yes: Reference: B4-(1)

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Disclaimer: The information in this document is believed to be correct in light of information currently available and at the time of publication but is not guaranteed. Neither LABC Warranty nor its agents can accept responsibility in respect of the contents or any events arising from the use of the information contained within this site. The guidance provided does not replace the reader’s professional judgement and any construction project should comply with the relevant Building Regulations or applicable technical standards. For the most up to date LABC Warranty technical guidance please refer to your Risk Management Surveyor and the latest version of the LABC Warranty Technical Manual.