Fire Stopping UK Guide (2025–2029) for Housing Providers & Responsible Persons
Housing providers and Responsible Persons carry legal duties to maintain effective compartmentation and prove it at audit. This Fire Stopping UK guide translates Approved Document B requirements into practical actions for English housing stock, highlights 2025 updates and the 2026/2029 changeovers, and shows how to evidence compliance under Regulation 38 with clear schedules, photos and commissioning records.
Last updated: 23 September 2025 - Fire Stopping UK guide
Fire Stopping UK guide - On this page :
- What “fire stopping” means for housing providers
- The England-only legal context you must follow
- 2025–2029: what changed and when to act
- Exactly where fire stopping is required in housing blocks
- Specification rules that prevent rework
- Installation QA for live schemes
- RP evidence pack that stands up to audit (Regulation 38)
- Worked housing examples (good practice)
- Frequently asked questions
- Soft CTA: need an RP-ready evidence pack?
What “fire stopping” means for housing providers
Fire stopping is the sealing of every joint, gap and service penetration in fire-separating elements (compartment walls/floors, protected enclosures) so that those elements keep their required fire resistance (for example, REI 60). Done right, fire stopping works alongside cavity barriers and fire/smoke dampers to contain fire and smoke, protect escape routes, and buy time for evacuation and firefighting.
Compartmentation goals
- Contain flame and smoke to the room/compartment of origin.
- Protect escape routes (stairs, lobbies, corridors) long enough for safe egress.
- Limit damage and disruption in multi-residential buildings.
Fire stopping vs cavity barriers vs dampers
- Fire stopping: seals penetrations and linear joints in rated walls/floors.
- Cavity barriers: subdivide concealed voids; minimum performance typically E30 / I15 (from each side).
- Fire/smoke dampers: prevent spread through ducts; smoke-linked closure on protected routes.
Definition: Fire stopping is the sealing of every joint, gap and service penetration in fire-separating elements so the wall or floor keeps its required fire resistance (e.g., REI 60). In housing, it works with cavity barriers and dampers to contain fire and smoke and protect escape routes.
- Use proprietary, tested systems that match the element’s rating.
- Keep openings as small as practicable; seal to full depth.
- Plastic pipes: collars/wraps or diameter/sleeve rules per tested systems.
- Fit fire & smoke dampers at protected routes; interlock to smoke detection.
- Label and photograph every penetration; compile a Regulation 38 pack.
The Legal Context - Fire Stopping UK Guide
Building Regulations & Approved Document B (ADB)
In England, the Building Regulations set the legal requirements and Approved Document B (ADB) provides guidance on ways to comply. For dwellings and common parts in blocks of flats, ADB Volume 1 is your primary reference. Fire stopping flows from the intent of requirement B3 (internal fire spread - structure) and the performance tables that define what “resistance to fire” means for the various elements, doors and services.
Regulatory Reform (Fire Safety) Order 2005
The Fire Safety Order imposes ongoing duties on the Responsible Person (RP) for common parts of residential buildings. In practice, that means maintaining compartmentation and proving—with evidence—that fire-separating elements and their penetrations remain effective over time. This guide shows how to assemble the records an RP will be expected to produce at audit.
Regulation 38 Handover Information
Regulation 38 requires handover of key fire-safety information on completion so the building can be operated safely. For fire stopping, that includes as-built compartment drawings, penetration/cavity-barrier schedules, damper commissioning, and product documentation (DoPs, test references) - all mapped to locations the Responsible Person can inspect and maintain.
2025–2029: what changed and when to act
2025: strengthened expectations & classification alignment
Recent editorial changes to ADB reinforce the need for robust Regulation 38 deliverables and continue the sector’s shift to BS EN 13501 classifications (reaction to fire, roofs, fire resistance). Update standard specifications and notes now to remove reliance on legacy national classes.
From 30 September 2026: second stair & evacuation lift design impacts
For blocks of flats where a storey is 18 m or more, ADB recommends more than one common stair and introduces provisions to support evacuation lifts. This reshapes protected route strategy, often increasing the number of lobby penetrations, doorsets and services interfaces - all of which depend on correct fire stopping and damper placement.
From 2 September 2029: national classes withdrawn
ADB’s tables phase out the national (BS 476) classes by 2 September 2029. After that, specify and evidence to EN-only classifications (REI/EI for resistance; A1–F and BROOF(t4) etc. for reaction to fire/roofs). Future-proof your portfolio by adopting EN classifications across all projects now.
Exactly where fire stopping is required in housing blocks
Penetrations: pipes, cables, trays
Any opening through a compartment wall/floor must be sealed so the element maintains its rating. In practice, you have three compliant strategies:
- Proprietary tested systems (preferred): collars, wraps, batts, sealants and accessories configured exactly as tested for the wall/floor build-up and service type/diameter.
- Diameter-limited approach: where permitted, some plastic/metal pipes can pass if the nominal internal diameter is within the relevant limits and the opening is fire-stopped to the smallest practicable size.
- Sleeving: use a high-melting-point metal sleeve in contact with the pipe, installed to the tested geometry.
Whichever route you take, label the penetration, record the system details, and photograph before/during/after installation for the RP pack.
Ducts and dampers on protected routes
Do not allow HVAC systems serving protected stairways to interconnect with other spaces. Where ductwork enters or leaves a protected route (stairs, lobbies, corridors), provide the correct fire & smoke damper type and interlock it to smoke detection. Commission and record actuation tests, then include certificates in the evidence pack.
Linear joints and junctions
Seal linear gaps (e.g., head of wall, perimeter edges) with tested systems that match the element’s rating. Where compartment walls meet roofs, continue the fire-stopping to the underside of the covering, apply the appropriate rated bands, and protect roof members where they pass through the wall.
Cavity barriers in concealed spaces
Cavities are highways for smoke and flame. Provide cavity barriers to divide cavities and close edges, with minimum performance typically E30 / I15 from each side. Fix robustly to rigid construction; if the substrate is irregular, fire-stop the junction as well. Limit openings through cavity barriers to permitted items (e.g., E30 doors, compliant pipes, suitable ducts/dampers/cables).
Specification Rules
Keep the element’s rating (REI/EI)
Fire-stopping must maintain the same fire resistance as the wall/floor it penetrates. If a compartment floor is REI 60, the seal around every service must collectively achieve that performance for the exact configuration.
Plastic pipe strategy
For thermoplastics, proprietary intumescent collars or wraps are typically required. If you cannot use a proprietary system, you may be able to rely on diameter limits or sleeving — but only where the guidance allows and the solution is proven for your wall/floor type.
Movement, fixings, irregular substrates
Account for structural and thermal movement, potential collapse of services, and failure of weak fixings under fire. Do not assume “mastic solves everything”: large or complex openings usually require batts plus wraps/collars, installed to the manufacturer’s detail including fasteners, edge distances and seal depths.
Future-proofing to 2029 and beyond
Remove national class references from specifications. Use EN classifications for resistance, reaction to fire and roofs now to avoid re-designs later. Align any internal standard details and schedules to EN terminology (REI, E, I; A1–F; s/d smoke and flaming classifications).
Installation QA
Before installation
- Approve manufacturer details and field-of-application/EXAP for each service/element combination.
- Coordinate penetrations on plans/sections; assign unique IDs and expected systems.
- Brief installers: orientation matters (exposure side, wall vs floor build-ups).
During installation
- Keep openings to the minimum practicable size; seal to full depth of the element.
- Install collars/wraps/batts exactly as tested; do not mix components across systems.
- Label every penetration and capture photos: before, during, after.
Commissioning and records
- Test fire/smoke damper actuation on smoke signal at each protected route boundary.
- Record test results, serial numbers and locations; file certificates in the RP pack.
- Cross-check labels to the penetration schedule before closing ceilings/finishes.
Common failure modes
- Relying on sealant alone for large or multi-service openings.
- “Like-for-like” swapping of collars or wraps without evidence.
- Missing cavity barriers above suspended ceilings or behind façade zones.
- Dampers present but not smoke-linked or not commissioned.
RP evidence pack that stands up to audit (Regulation 38)
Your Regulation 38 handover should make it easy for the RP to locate, understand, inspect and maintain every element of compartmentation. Include the following as a minimum:
| Penetration ID | Unique label matching drawings and photos. |
| Location | Building, floor, room/riser; grid/chainage where helpful. |
| Element & rating | e.g., REI 60 wall, REI 90 floor; thickness and build-up. |
| Services | Type, quantity, materials and diameters (e.g., 110 mm uPVC waste, 2 × cable trays). |
| System used | Manufacturer, kit name/model, EXAP/ETA reference; orientation details. |
| Installation | Installer, date, sign-off initials; fastener types/centres where relevant. |
| Photos | Before (substrate), during (packing/fixings), after (finished seal/label). |
| Documentation | DoP/CoC file references; O&M link; maintenance notes. |
| Notes | Movement joint present? Acoustic coupling? Special constraints? |
As-built fire strategy drawings
Provide clear compartment lines, protected routes, shafts and the fire-resistance ratings of walls/floors. Indicate where dampers, cavity barriers and key penetrations occur.
Inspection & maintenance cadence
- Quarterly: visual checks of accessible penetrations and labels.
- Annually: sample intrusive checks in risers/voids; damper actuation tests.
- 5-yearly: broader intrusive review of high-risk zones (stair/lobby risers, plant).
Worked housing examples (good practice)
Plastic waste stack through an REI 60 compartment floor
Use a proprietary, tested configuration of collar/wrap plus batt and sealant, installed to the exact detail for floor thickness and pipe diameter. If a proprietary system is not available, confirm whether diameter-limited or sleeved solutions are permitted for your construction and ensure the opening is kept to the minimum practicable size.
Duct crossing a protected lobby
Provide a fire & smoke damper at the boundary. Interlock to smoke detection so the damper closes on alarm. Commission and record the test; include certificates in the RP pack. Ensure the damper classification aligns with the wall/floor rating.
Compartment wall meeting pitched roof in low-rise
Continue the fire-stopping to the underside of the roof covering, apply rated bands, and protect roof members passing through the wall. Verify the junction detail is compatible with the roof system and any cavity barriers above ceilings.
FAQs - Fire Stopping UK Guide
Do I need proprietary tested systems for every penetration?
Yes. For most mixed-service openings, proprietary systems are the most reliable way to maintain the wall or floor’s fire resistance. Avoid mixing components outside the tested scope.
Can I rely on mastic for large openings?
Generally no. Intumescent sealant alone is rarely adequate for larger or multi-service holes; you’ll typically need batts plus wraps/collars as per the system test and installation manual.
What changes between 2025 and 2029 should I design for now?
Move to BS EN 13501 classifications across fire resistance, reaction to fire and roofs. National classes are withdrawn in September 2029, so EN-only specifications avoid retrofit and rework.
How should an RP evidence compliance at handover and beyond?
Provide a Regulation 38 pack with as-built compartment drawings, penetration/cavity-barrier schedules tied to labels and photos, product documentation, and damper commissioning records.
When do dampers need smoke-linked closure?
Where ducts enter or leave protected routes (stairs, lobbies, corridors). Ensure the correct damper type/classification, smoke-linked actuation, and commissioning records.
What’s the minimum for cavity barriers in housing stock?
As a rule of thumb, E30 / I15 performance from each side with robust fixings. Limit openings through barriers to permitted items (e.g., E30 doors, compliant pipes/ducts/dampers/cables) and fire-stop irregular junctions.
Need a hand compiling an RP-ready evidence pack?
We’ll audit your existing housing stock, produce a gap list, and deliver penetration & cavity-barrier schedules with photos, DoPs and commissioning records - aligned to current ADB and ready for regulator or landlord scrutiny.
Anstey Horne provides comprehensive, accredited compartmentation and fire stopping assessments tailored to every building type. Our experts help you stay compliant, reduce risk, and protect lives.
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For further information on Fire Stopping, Compartmentation, Fire Door Surveys or advice in respect of your obligations as a responsible person, building owner, developer or manager, please contact :
Tony Leishman
BSc (Hons) FRICS C.Build.E MCABE MIFireE MIFSM
Senior Director
Fire Consultancy
Manchester
Sarah Taylor
Business Support Manager
Building Surveying
London