P2-8 Response Accepted

Require fire engineer calculations for fire spread and evacuation

Recommendation

Calculating the likely rate of fire spread and the time required for evacuation, including the evacuation of those with physical or mental impairments, are matters for a qualified fire engineer. We do not think that it would be helpful to attempt to include in Approved Document B an indication of what would be acceptable because each building is different, but we recommend that the guidance draw attention to the need to make a calculation of that kind. (113.13)

Published Evidence Summary
The following publicly available evidence relates to this recommendation:
The government accepted this recommendation in February 2025, stating it would be addressed through the ongoing Building Safety Regulator (BSR)-led review of Approved Document B. A gov.uk progress update from February 2026 reports that fire spread guidance development is occurring through this review, with industry engagement exploring enhancements to external wall fire spread guidance.
How was this evidence gathered?
Evidence searched by gemini-2.5-flash on 24 Mar 2026
Checked data held on this site (government responses, progress updates, independent evidence)
External sources searched: www.gov.uk, www.legislation.gov.uk, hansard.parliament.uk
Jurisdiction
England
Response
Accepted
Accepted UK Government Initial Response
16 Jan 2025

The government accepts this recommendation. We will address this recommendation through the ongoing Approved Document B review, led by the Building Safety Regulator. The review and industry engagement will explore ways through which Approved Document B can be updated to provide further guidance on external fire spread, while sufficiently supporting designers in considering fire spread via the external wall.

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Accepted UK Government Follow-up
26 Feb 2025

The government accepts this recommendation. We will address this recommendation through the ongoing Approved Document B review, led by the Building Safety Regulator. The review and industry engagement will explore ways through which Approved Document B can be updated to provide further guidance on external fire spread, while sufficiently supporting designers in considering fire spread via the external wall.

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Progress Timeline
Official Report
01 Feb 2026

Fire spread guidance development occurring through the ongoing Approved Document B review, led by the Building Safety Regulator. Industry engagement exploring external wall fire spread guidance enhancements. (Covers Recommendations 5, 6, 7, 8, 9, 11, 12.)

Source
Report Grenfell Tower Inquiry: Phase 2 Report 04 Sep 2024
Responsible Bodies
UK Government Primary
Recommendation age 1.6 yrs
Last formal update 01 Feb 2026