A fire stopping specialist installs passive fire protection (PFP) to seal gaps, holes and service penetrations through fire-rated walls, floors and partitions. Their work maintains fire compartmentation required by Building Regulations Approved Document B - dividing buildings into compartments that limit the spread of fire and smoke and provide time for evacuation. Under the Building Safety Act 2023, the fire stopping audit trail in higher-risk buildings (HRBs) must be documented and maintained throughout the building's life. Competent fire stopping is achieved only through third-party certified contractors using tested and certificated product configurations.
What they do
- Seal cable penetrations through fire-rated walls and floors
- Install intumescent collars and wraps on plastic pipe penetrations
- Install cavity barriers in wall and floor cavities
- Seal linear joints between fire-rated elements
- Install fire door intumescent strips and smoke seals
- Install fire-rated service duct closers and dampers
- Carry out compartmentation surveys and remediation
- Produce photographic installation records for the Building Safety Act golden thread
When you need one
A fire stopping specialist is needed whenever services penetrate fire-rated elements in a building, or when existing compartmentation is found to be defective or incomplete.
Typical costs (UK, 2025)
| Job type | Typical cost |
|---|---|
| Cable penetration seal (per penetration) | £50 - £150 |
| Intumescent collar on plastic pipe (per collar) | £80 - £200 |
| Compartmentation survey (per floor) | £500 - £2,000 |
| Fire stopping remediation (per day) | £600 - £1,200 |
| Full compartmentation survey and remediation (HRB) | £10,000 - £100,000+ |
| Fire door inspection and remediation (per door) | £150 - £500 |
Remediation costs for buildings with widespread compartmentation failure (common in post-1960s residential blocks) can be substantial. Costs depend heavily on access (especially to ceiling and floor voids) and the quantity of penetrations requiring treatment.
Qualifications to look for
The ASFP operates the Passive Fire Protection Installer and Compartmentation Inspector schemes, which require training, assessment and annual audit. ASFP membership and accreditation is increasingly required for fire stopping work on higher-risk buildings. Check the ASFP register at asfp.org.uk.
IFC certification confirms competence in the correct installation of intumescent fire stopping products to tested and certificated configurations. IFC-certified installers must use products within their assessed scope and produce installation records. Check at ifc.org.uk.
How to find a reputable fire stopping specialist
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What is fire stopping and why is it important?
Fire stopping is the installation of passive fire protection materials to seal gaps, holes and service penetrations through fire-rated walls, floors and partitions. The purpose is to maintain fire compartmentation - dividing a building into fire compartments that slow the spread of fire and smoke. Building Regulations Approved Document B requires compartmentation to be maintained even where services (pipes, cables, ducts) pass through fire-rated elements. Breaches in compartmentation are one of the most common defects found in fire risk assessments and Building Safety Act audits of multi-storey buildings.
What fire stopping products are used?
Fire stopping products include intumescent seals (which expand when heated to seal gaps), intumescent collars and wraps (for plastic pipes that melt in fire, leaving a gap that needs sealing), fire-rated sealants (acrylic and silicone based), fire-rated mortar infills, mineral wool and fire boards. The correct product depends on the type of penetration, the fire resistance rating required and the wall or floor construction. Products must be used in tested and certificated configurations - mixing products from different manufacturers in an untested configuration can invalidate the fire resistance.
What certification should a fire stopping contractor have?
Look for IFC certification (Intumescent Fire Seals Association) or ASFP (Association for Specialist Fire Protection) membership and third-party accreditation. The ASFP operates the Passive Fire Protection Installer scheme and the Compartmentation Inspector scheme. BM TRADA Q-Mark is another widely recognised scheme. Third-party certification is strongly recommended for Building Safety Act compliance in higher-risk buildings, where a complete passive fire protection audit trail is required.