Trades master copy
Last reviewed: March 2026
What Part 7 is
Regulation 7 is the materials and workmanship rule that sits under everything else. It says: use proper materials and do the work in a workmanlike way so the building actually meets the other Parts.
It also now locks in the non-combustible materials requirement for external walls of certain high-rise/high-risk buildings (linking to the post-Grenfell rules alongside Part B).
This guide is a summary to make Regulation 7 easier to use on site. It does NOT replace Regulation 7 of the Building Regulations or its associated guidance.
You must use materials and workmanship appropriate to the job, in line with the manufacturer's instructions and current standards.
This guide is written for England. Wales, Scotland and Northern Ireland have their own versions of building regulations - the principles are similar but the documents and approval routes differ, so check local requirements if you're working outside England.
Where it applies on your jobs
Every job, every trade:
- New builds, extensions, refurbs, conversions - if it's "building work" under the regs, Regulation 7 applies.
Materials must be:
- Suitable for the job.
- Correctly CE/UKCA-marked or otherwise shown suitable.
- Used as the manufacturer intended.
On taller "relevant buildings" (e.g. residential over 18 m), materials forming parts of external walls or "specified attachments" generally need to be non-combustible (A2-s1, d0 or A1) - that's where Regulation 7(2) bites alongside Part B.
Key "trigger points" - what matters on site
- Swapping specified products: going cheaper/thinner/different without checking certification or design sign-off.
- Using kit off-label: waterproofing, fire-stopping, insulation, sealants used in the wrong place or build-up.
- External wall works on taller blocks: cladding/insulation choices must meet Regulation 7(2), not just "look OK".
Simple rule for the team
If you're changing what you're building with, or how you're using it, you're playing with Regulation 7. Stick to the spec and manufacturer data, and on taller/external wall jobs, assume you need non-combustible materials unless the designer tells you otherwise in writing.
This guide was last reviewed March 2026. SiteKiln does not provide legal, financial or tax advice. All content is for general information purposes only. Always seek professional advice for your specific situation.
Know someone who needs this?
Working in Wales? The building rules are different. See our Working in Wales guides.
Working in Scotland? Building standards work differently. See our Working in Scotland guides.
Working in Northern Ireland? The system uses Technical Booklets. See our Working in Northern Ireland guides.
Was this guide useful?
Didn't find what you were looking for?
Spotted something wrong or out of date? Email us at hello@kilnguides.co.uk.
In crisis? Samaritans 116 123 ·