Slab Edge and Compartmentation
A Guide to Superior Fire-Stopping Solutions
At BSML, we help building owners, designers, and contractors achieve robust passive fire protection from the earliest design stages through to project handover. One of the most critical, yet often misunderstood, areas is the treatment of slab edges and the integrity of compartmentation.
Why Slab Edge Fire-Stopping Matters
The junction between the edge of a floor slab and the external or internal facade can act as a concealed pathway for fire and smoke. Poorly designed or installed fire-stopping at slab edges can undermine an otherwise compliant fire strategy.
Effective slab edge solutions help to:
- Maintain compartmentation between floors
- Limit the vertical spread of fire and smoke
- Protect escape routes and firefighting shafts
- Support overall compliance with Building Regulations and fire strategy reports
Understanding Compartmentation
Compartmentation divides a building into fire-resisting sections to contain fire at its source. Slab edges are a key part of these fire compartments and must be treated with the same rigour as walls, doors and service penetrations.
A strong compartmentation strategy at slab edges should:
- Match or exceed the fire resistance of the adjacent elements
- Address all gaps, voids and interfaces with facades and curtain walling
- Integrate with cavity barriers, fire-rated sealants and insulation systems
Typical Slab Edge Challenges
Common risks we encounter on site include:
- Gaps between floor slabs and facades that are left unsealed or loosely filled
- Incompatible materials used together (e.g. non-fire-rated insulation in critical gaps)
- Missing or incorrectly installed cavity barriers
- Design details that do not reflect tested fire-stopping systems
These issues can compromise performance in a fire test scenario, even if individual products are certified.
Fire-Stopping Solutions from BSML
At BSML, we focus on tested systems, correct detailing and high-quality installation. Our slab edge and compartmentation services typically include:
Design review and coordination
- Checking drawings and specifications for compliance
- Proposing tested details for slab edge/facade interfaces
Product selection
- Non-combustible or fire-resisting boards and insulation
- Tested curtain wall fire-stop systems
- Fire-resisting sealants, sprays and coatings
Installation and quality assurance
- Skilled, third-party-accredited installers
- On-site inspections and photographic records
- Clear labelling and documentation for handover
Key Best Practices
To achieve superior slab edge and compartmentation performance, we recommend:
- Contact passive fire specialists early in the design process
- Use only third-party-tested and approved systems
- Ensure continuity between slab edge fire stops, cavity barriers and compartment walls
- Maintain accurate records for future inspections and maintenance
How BSML Can Help
From new build to refurbishment, BSML provides a complete, compliant and practical approach to slab edge fire-stopping and compartmentation.
To discuss your project, drawings or site challenges, get in touch. Our team of passive fire protection specialists are ready to support you with clear advice.
The information provided in this article is for general guidance only and is not legal or professional advice.