What would happen if smoke filled the corridor of a residential building before residents could escape? It’s a chilling question, and one the updated fire safety standard BS 9991:2024 tackles head-on. This latest version introduces some of the most important changes in smoke control strategy in over a decade.
If you’re involved in designing, building, or managing residential spaces, it’s time to rethink your approach to smoke ventilation. These changes aren’t just box-ticking exercises; they’re about making homes safer and lives more secure.
What’s Changed? A Quick Overview
BS 9991:2024 is a big step forward. It brings in firmer rules and wider responsibilities, especially for higher-risk settings like care homes and taller buildings. Unlike previous editions, this update removes ambiguity around smoke control. It doesn’t leave much room for interpretation anymore: there’s now a clearer push for performance-based systems that work under real fire conditions.
Some of the biggest updates include:
● Residential care homes included – Recognising their distinct needs.
● Stricter rules on smoke ventilation – Active systems are now mandatory in many areas.
● PEEPs (Personal Emergency Evacuation Plans) – Now essential for inclusive fire safety.
● Tighter control over materials – Especially for timber structures and fire doors.
● New limits on single stairway buildings – Height now capped at 18 metres.
Why Smoke Ventilation Is a Priority
Smoke, not flames, is the leading cause of death in building fires. That’s why BS 9991:2024 shifts its focus to active smoke control in corridors, lobbies, and other common spaces.
The new fire safety standards BS 9991 for smoke vents place greater weight on ensuring smoke can be quickly extracted or contained, allowing people time and space to evacuate safely. The document now mandates coordinated systems. So, smoke detectors, vents, and controls must work together. No more standalone units operating in isolation. It’s a joined-up approach that reflects how fires behave and how buildings must respond.
Building Height Matters
The updated standard introduces tiered guidance based on building height. Here’s a breakdown of how smoke ventilation requirements now shift depending on elevation:
● Up to 18m – Active smoke ventilation is mandatory in lift lobbies. Systems must stop smoke ingress without direct extraction from the lobby itself.
● 18m to 30m – Natural AOVs (Automatic Opening Vents) are no longer permitted. You need properly engineered mechanical systems.
● 30m to 60m – At this level, mechanical systems or pressurisation become essential. Natural shafts aren’t enough.
● Over 60m – Systems must follow pressure differential standards, ensuring consistent airflow to protect escape routes.
This new tiered structure highlights a key shift: assumptions are no longer good enough. You need evidence-based design, and your strategy has to match the risks that come with building height.
A Push for Inclusive Design
Another crucial change in BS 9991:2024 is the emphasis on Personal Emergency Evacuation Plans (PEEPs). Fire safety can’t assume a one-size-fits-all approach. People with reduced mobility, sensory impairments, or cognitive conditions need tailored strategies that don’t rely solely on personal capability.
This means extended evacuation windows, fail-safe system design, and communication options that work for all users.
In other words, you must plan for everyone, not just the able-bodied majority. Whether you’re specifying smoke vents or designing building layouts, inclusivity must be part of the process from the start.
Residential Care Homes Brought into Scope
Until now, residential care homes were often overlooked in BS 9991. That’s changed. Section 10 explicitly brings these facilities under its guidance. Given the nature of care home residents, often elderly or with limited mobility, this inclusion is long overdue.
The implication? You’ll need to apply all other parts of the standard, including smoke control, evacuation lifts, and PEEPs, with extra attention in these buildings. Fire strategies here must be both robust and compassionate.
Tightened Control on Sprinklers, Lifts, and Doors
Several updates focus on hardware, including sprinkler systems, evacuation lifts, and fire doors. Let’s look at what’s changed:
Sprinklers
● Required in any building above 11m.
● For buildings over 18m, sprinklers are compulsory and must follow Category 4 of BS 9251.
● Ancillary areas above 100m² must comply with BS EN 12845.
Evacuation Lifts
● Every escape stair should ideally have an evacuation lift.
● Lifts must open into protected lobbies or stairs with equivalent smoke protection.
● Above 50m? Every lift should double as a firefighting lift.
Fire Doors
● New fire doors must meet EN 13501-2 standards.
● All doors require four-sided smoke seals under Sa4 classification.
These measures go hand-in-hand with smoke ventilation systems to create layered protection. It’s no longer acceptable to install one or two components in isolation.
Limits on Open Plan Designs
The new rules also clamp down on open-plan layouts. While they’re popular for aesthetics and natural light, they come with real fire risks, especially around kitchens.
Now, open-plan flats are capped at 16m x 12m. Cooking appliances must be kept at a safe distance from escape routes. The goal is to stop fires in kitchens from cutting off people’s only way out.
What This Means for You
Whether you’re an architect, a contractor, or managing a residential portfolio, these changes demand immediate attention. Relying on outdated assumptions or older standards won’t cut it in 2025. And while compliance is a legal responsibility, there’s a broader moral one too: ensuring that every resident, visitor, and staff member has a safe route out if the worst happens.
Here’s what to focus on moving forward:
● Review current designs against height-based ventilation requirements
● Reassess all escape strategies with inclusive evacuation in mind
● Check that all fire doors, lifts, and sprinkler systems meet the updated technical standards
● Collaborate with competent professionals who understand the 2024 standard inside-out
Time to Rethink the Basics
BS 9991:2024 isn’t just an update. It’s a shift in mindset. It asks everyone involved in residential building design and safety to stop relying on assumptions, patchwork solutions, or outdated guidance.
This is your prompt to step back and take a fresh look. Does your current smoke ventilation approach still make sense? Are the systems in place designed for performance or convenience? And most importantly, are they protecting the people who need them most?
Now’s the time to make those changes. Because when smoke begins to spread, every second counts.
