For years, fire resistance in England has been shown in one of two ways: the older British Standard BS 476 national classes, or the European classification under BS EN 13501-2. That dual route is ending. References to the BS 476 national classes are being removed from Approved Document B from 2 September 2029. This article explains what that means for specifiers, contractors and owners dealing with fire-rated sealants.
What is changing
After the change, the European classification under BS EN 13501-2 becomes the route for showing fire resistance under Approved Document B, subject to the Government’s transitional arrangements. Products that rely only on BS 476 test evidence will need European test evidence and classification to be used under the guidance. You can read the guidance itself on the Approved Document B page, and a summary of the change in this Socotec article on the removal of BS 476.
How fire-rated sealants are tested under the European route
- BS EN 1366-3 covers penetration seals: where pipes, cables and ducts pass through fire-resisting walls and floors (BSI).
- BS EN 1366-4 covers linear joint seals: gaps along the edges of walls and floors.
- BS EN 13501-2 classifies the results. E stands for integrity and I for insulation, each with a time in minutes, such as EI 60 or EI 120.
What it means for specifications
Specifications that still quote BS 476 will need updating. Specifiers should check that each fire-rated sealant and detail they name has evidence and a classification under the European route. The detail must match the real situation: the substrate, service type and size, gap, depth, backing and orientation. A product with a good classification in one configuration is not proven for another. Our fire-rated vs intumescent guide explains why.
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What it means for existing buildings
The change concerns the guidance for building work. It does not, in itself, mean every existing seal must be replaced. Owners should take advice from their fire risk assessor or fire engineer about their own buildings. When new work is carried out, such as new services through a compartment wall, the seals used should follow the guidance in force at the time.
Where existing records show seals tested only to BS 476, note them. That information will help the fire risk assessor and anyone planning future work in those areas decide what, if anything, needs doing.
Practical steps and supplier questions
- Review standard specifications and details that quote BS 476.
- Ask product manufacturers for their European test evidence and classifications.
- Keep data sheets and evidence with your fire stopping records.
- Check projects that will run past the date for transitional arrangements.
Scotland has its own building regulations and handbooks; see fire stopping and Scotland’s building standards.
- Does this fire-rated sealant have test evidence under BS EN 1366-3 or BS EN 1366-4 for our situation?
- What classification under BS EN 13501-2 does it achieve, and in which configuration?
- Which substrates, service types and sizes, gap widths and depths does the evidence cover?
- What backing material does the detail need?
- Is the installation guidance available in writing?
Clear answers make the change straightforward. If a product can’t show evidence for your detail, the designer should consider an alternative.
Where we fit in
We install fire-rated and intumescent sealant where it is specified, to the product’s tested detail. We don’t choose the classification or sign off compliance; that sits with the designer, fire engineer and building control. See our fire-rated sealing page.
Quick answers
Does BS 476 stop applying on 2 September 2029?
References to the BS 476 national classes are being removed from Approved Document B from that date, with the European classification becoming the route, subject to the Government’s transitional arrangements.
Do I need to replace existing fire stopping?
Not automatically because of this change. Take advice from your fire risk assessor or fire engineer on your own building.
Does this apply in Scotland?
Approved Document B is guidance for England. Scotland has its own building regulations and technical handbooks, which should be checked separately.
Related services
More advice
- Fire-Rated vs Intumescent Sealant Explained
- Fire Stopping Explained for Building Owners
- Building Safety Act and Fire Stopping Records
- Fire Stopping and Scotland's Building Standards
- All advice
This guide is general information about sealant work. It isn’t legal, fire-safety or structural advice; for those, speak to a qualified professional.