An AOV system — Automatic Opening Vent — is a critical component of fire safety in many buildings. When a fire alarm activates, AOV systems automatically open vents, roof lights or windows to allow smoke and heat to escape, keeping escape routes clear and buying vital time for safe evacuation. All our AOV and smoke ventilation systems comply with Building Regulations Approved Document B and BS EN 12101. For local installation across Kent see our AOV systems Kent page, or for Sheerness our AOV systems Sheerness page.
What is an AOV system and why is it needed?
Automatic Opening Vent systems consist of roof lights, windows or vents linked to the fire alarm control panel, which open automatically on activation. This prevents smoke from accumulating in stairwells, corridors and escape routes — the primary cause of fatalities in building fires. AOV systems are now required in many residential and commercial buildings under Building Regulations, and are increasingly required in existing buildings undergoing renovation or change of use.
- Automatic smoke clearance linked to fire alarm activation
- Keeps stairwells and corridors clear for safe evacuation
- Assists fire service operations on arrival
- Required in many buildings under Approved Document B
- Manual override controls at ground floor level
AOV systems for residential buildings
Blocks of flats, houses in multiple occupation (HMOs), sheltered housing and care homes frequently require AOV smoke ventilation systems under Building Regulations. We design and install AOV systems tailored to each residential building's layout, integrating with the existing fire alarm system for automatic operation on activation.
Commercial smoke ventilation systems
Offices, hotels, retail premises, schools and healthcare buildings require effective smoke control systems as part of their fire safety strategy. We design and install commercial smoke ventilation systems including powered smoke extract fans, pressurisation systems and smoke reservoirs — all complying with BS EN 12101 and Approved Document B.
AOV maintenance and servicing
Regular maintenance of AOV systems is essential to ensure correct operation when needed. We offer AOV maintenance contracts covering annual functional testing and full certification. Weekly manual tests and annual engineer-led maintenance visits are both covered under our service agreements. Alongside AOV maintenance, we recommend annual servicing for your fire alarm system, emergency lighting and fire doors.
Frequently asked questions
AOV systems are typically required in buildings with enclosed staircases including blocks of flats, HMOs, offices, hotels and sheltered housing. Approved Document B provides guidance — our engineers can advise for your specific building.
AOV systems link directly to the fire alarm control panel so designated vents open automatically on activation. They can also be manually operated from a control switch.
AOV systems should have a full functional test by a qualified engineer at least annually, with weekly manual tests recommended. Our maintenance contracts cover both.
Yes — we can design and install AOV and smoke ventilation systems in both new and existing buildings, working around the existing structure to minimise disruption.