When a fire breaks out, it is often the smoke that makes escaping difficult. It can spread quickly through corridors, lobbies and stairwells, reducing visibility and cutting off escape routes. This is why smoke ventilation regulations are so important: they help ensure buildings have suitable systems in place to control smoke and heat, protect occupants and support firefighters.
Working out what regulations apply, is not always straightforward. There is no single piece of UK smoke ventilation legislation covering every building or system. Instead requirements come from a combination of building regulations, fire safety legislation, British standards and the buildings fire strategy.
In this guide, we will break down some of the main smoke vent regulations in the UK and explain what they mean in practice. If you need further guidance, our smoke ventilation specialists are here to help.
| Standard | Purpose |
|---|---|
| Approved Document B | Guidance for when smoke ventilation is required and what the system needs to achieve |
| BS EN 12101 | A series of product standards that sets the testing, performance and certification requirements for smoke vent products |
| BS 9991 | A British standard providing more detailed, flexible, risk based fire safety design guidance for residential buildings |
| BS 9999 | Similar to BS 9991 but for non residential buildings, allowing for an alternative approach especially for more complex buildings |
| BS 7346-8 | British Standard that provides guidance on the installation, commissioning, testing, maintenance, and ongoing operation of smoke ventilation systems. |
| Regulation 38 | Requires the relevant fire safety information to be handed over to the person responsible for the building |
| Building Safety Act 2022 | Introduces greater accountability for building safety, particularly in higher-risk buildings, |
Smoke Ventilation Building Regulations & Approved Document B
The Building Regulations 2010 is the legal fire safety requirement for building work in England. Approved Document B provides practical guidance on ways to meet those requirements, including where smoke ventilation may be needed to protect escape routes and support firefighting. Approved Document B is guidance rather than the law itself and it is not the only possible route to compliance.
It sets out common arrangements for smoke ventilation routes, including where vents should be positioned, how they should operate and the minimum free vent areas.
The guidance is a recognised way of demonstrating compliance, but the exact smoke ventilation requirements will vary depending on the building’s use, layout, evacuation strategy and fire strategy.
AOV and Smoke Vent Requirements
Automatic opening vents (AOVs) open when a fire is detected to create a route for a smoke and heat to escape through an AOV window, roof vents or smoke vent louvre.
Fitting an actuator to a standard window doesn’t automatically create a compliant AOV. The complete assembly, including the vent, actuator, frame, profiles, hardware and infill, must be tested together under BS EN 12101-2.
The manufacturer’s Declaration of Performance (DoP) records the product’s performance, confirming that it:
- Is tested through the required number of operating cycles, with higher cycle testing where the AOV is also used for daily ventilation
- Opens to its fire position, typically within 60 seconds
- Continues operating at high temperatures for its declared period
- Tested against its declared wind and snow load classes
- Provides the required aerodynamic free area for smoke to pass through
A certification and a DoP doesn’t automatically mean an AOV is compliant for every building. It must meet the requirements of the projects fire strategy and application. View more detail about AOV regulations.
Smoke Ventilation Requirements Under BS 9991 & BS 999
BS 9991 and BS 9999 provide wider fire safety guidance for different types of buildings
- BS 9991 applies to residential buildings like flats and care homes
- BS 9999 applies to non residential buildings such as offices and industrial premises.
Both standards offer a more flexible, risk based approach to fire safety design. They consider factors such as the buildings use, occupancy, layout, escape routes and evacuation strategy. This flexibility can support more complex building designs.
Handover and Ongoing Smoke Vent Compliance
Regulation 38 requires relevant fire safety information to be handed over to the person responsible for the building. It should include things like
- The cause and effect strategy
- As installed drawings
- Product specs and DoPs
- Commissioning and test records
- Operating and maintenance requirements
Once the building is occupied, the Regulatory Reform (Fire Safety) Order 2005 requires fire safety equipment ti be kept in efficient working order. BS 7346-8 also provides recommendations for the testing, inspection and maintenance of smoke control systems.
Meeting UK Smoke Ventilation Regulations
Smoke Ventilation compliance involves more than selecting certified products. The best starting point is usually the buildings fire strategy. This should establish what the system needs to achieve. Considering smoke ventilation early in a project can help prevent expensive changes later.
Other regulations, standards and guidance may apply depending on the building and project. This is why it is important to work with experienced smoke ventilation specialists who can understand the fire strategy and help identify a suitable, compliant system.
