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AOV Installation & Upgrades
AOV and smoke vent installation and upgrades to BS 7346-8 by IFC SDI 19 certified engineers, tested against the cause and effect, across London.
New AOV systems, panel and actuator replacements and full upgrades, installed by our own engineers while residents stay at home, commissioned against the cause and effect and handed over ready for the golden thread.
Many AOV systems in blocks of flats have been in place for many years. Control panels go into fault, actuators wear out, cabling degrades and the link to the fire alarm no longer does what the fire strategy expects. Some systems have been altered so many times that nobody can say for certain which detector opens which vent.
Fire Systems Ltd installs new AOV and smoke control systems and upgrades existing ones for housing associations, local authorities and commercial clients across London and the South East. Because we also look after the fire alarms that trigger them, we design and test the whole sequence, from the detector in the lobby to the vent at the top of the stair.
Once the system is in, we can maintain it too: see AOV servicing and repairs.
Certified to Install Smoke Control (IFC SDI 19)
Fire Systems Ltd is certified under the IFC Certification SDI 19 scheme for the installation, commissioning and maintenance of smoke control systems (certificate IFCC 3453), audited by a UKAS-accredited certification body. We are members of the Smoke Control Association and NICEIC registered for the electrical work involved.
Our smoke control engineers work to BS 7346-8 and hold manufacturer training on the systems we install. On housing projects we act as Principal Designer and Principal Contractor under CDM 2015.
The Standards Behind an AOV Installation
BS 7346-8. The code of practice for planning, design, installation, commissioning and maintenance of smoke control systems.
BS EN 12101. The product standards for smoke control equipment, including natural smoke and heat exhaust ventilators (Part 2) and power supplies (Part 10).
BS 8519. The code of practice for fire-resistant cables that must keep working during a fire, which we follow when selecting smoke control cabling.
Approved Document B. Sets out when new and altered buildings need smoke ventilation to common stairs, corridors and lobbies, and how large the vents must be.
BS 9991 and BS 9999. The codes of practice for fire safety design of residential and non-residential buildings, including smoke ventilation.
CDM 2015. AOV installation is construction work, often at height and in occupied buildings, and needs proper planning and competent people in the Principal Designer and Principal Contractor roles.
What an AOV system includes
Control panels and power supplies. Networked AOV panels with standby batteries, so the vents still open if the mains supply fails.
Vents and actuators. Windows, roof vents, shaft vents and louvres, opened by chain or linear actuators sized for the vent.
Detection. Smoke detectors in the lobbies and corridors that trigger the right vent on the right floor.
Firefighter controls. Override switches that let the fire service open or close the vents manually.
Fire-resistant cabling. Cabling that keeps the system working during a fire.
Interfaces. Links to the fire alarm, door holders and any smoke shaft, set out in the cause and effect.
When an AOV System Needs Replacing
These are the situations where we are most often asked to replace or upgrade an AOV system.
Repeated faults: Panels that keep going into fault, open circuits and missing cabling, often down to the age of the installation.
Fire risk assessment actions: The assessor has found vents that do not open, interlocks that do not meet the standard, or a system that does not match the fire strategy.
Obsolete equipment: Panels and actuators that are no longer made, so repairs are slow, costly or impossible.
Higher-risk buildings: Buildings of 18m and over need smoke control that is checked monthly and fully documented for the golden thread.
Refurbishment: Window replacements, new doors or changes to the stair core that affect the smoke ventilation.
Not sure whether to repair or replace? We survey the system, test it against the cause and effect and give you a clear, costed recommendation for both options.
How We Install and Upgrade AOV Systems
Survey. We inspect the existing vents, actuators, panels, detection and cabling and test the system against the cause and effect.
Design. We design the replacement or new system to BS 7346-8, with safe access for future maintenance, and agree the cause and effect with you or your fire engineer.
Planning. Risk assessments and method statements, a Construction Phase Plan, access equipment and a programme that keeps the stairs usable.
Installation. Panels, actuators, detectors, firefighter switches and fire-resistant cabling installed while residents stay at home, with the old system live until the new one is commissioned.
Commissioning. Every vent opened and closed from every trigger and the whole system tested against the cause and effect, usually with your contract administrator or fire consultant present.
Handover. Design, installation and commissioning certificates, O&M manuals, logbook entries and a building plan showing every device, cable type and route and network schematic.
Why we test the AOV with the fire alarm
Most AOV systems are triggered by the fire alarm, or share its detectors. When different contractors install or maintain each system, both can pass their own tests while the link between them fails. We test the complete sequence at commissioning: detector, panel, vent, door holders, fire alarm and firefighter override.
Where there is no cause and effect, or it no longer matches the building, we produce one, so you have a clear record of what the system should do for your fire risk assessor and the golden thread.
“A faulty, non-compliant smoke vent system replaced across six storeys in four days, while residents stayed at home.”
Fire Systems Ltd surveyed, designed, installed and commissioned this AOV system for a London housing association in June 2023, testing it against the cause and effect to BS 7346-8.
Case Study: Replacing a Failing AOV System in a Six-Storey Residential Block
A London housing association asked us to look at an AOV system in a six-storey residential block that kept going into fault. Our design engineer surveyed the system and found open circuits and missing cabling, most likely down to the age of the installation. The building's smoke ventilation relied on six magnetically held doors, a vent at the head of the stairs and a vent at the top of the smoke shaft, and the interlocking between them did not meet the required standard.
Design. We recommended a full replacement and produced a design and detailed quotation. The new system comprised eight mains supplies, eight networked AOV control panels across six floors, eight chain actuators, seven smoke detectors and eight firefighter override switches. New cabling was selected to BS 8519, and the layout allowed for safe access for future maintenance.
Installation. Work started on 26 June 2023 and was completed in four days, with residents remaining in their homes throughout.
Commissioning. The client's contract administrator attended a full inspection, test and handover. We tested the operation of the system against the cause and effect schedule to BS 7346-8, then decommissioned and removed the old system.
Handover. We provided design, installation and commissioning certificates, manuals and operating instructions, logbook documentation, and a building plan showing every device, cable type and route and network schematic, so the client's golden thread records were complete from day one.
AOV Installation Questions We Are Often Asked
Should we repair or replace our AOV system?
If the panel and actuators are still supported and the faults are isolated, a repair is usually the right answer. If the system keeps going into fault, parts are obsolete or the interlocking does not meet the standard, replacement is usually cheaper over time. We survey and give you costed options for both.
Can an AOV system be replaced while residents stay at home?
Yes. We keep the stairs and corridors usable, keep the old system live until the new one is commissioned and work floor by floor. Our six-storey replacement was completed in four days with residents at home throughout.
What is a cause and effect?
A document that sets out exactly what happens when each device operates: which detector opens which vent, which doors release and what the fire alarm does. We commission every system against it and produce one where it is missing.
Do you install the fire alarm as well?
Yes. We are BAFE SP203-1 certified for fire alarms as well as IFC SDI 19 certified for smoke control, so one team can install and test both. See fire alarm design and installation.
What documents will we receive?
Design, installation and commissioning certificates, O&M manuals, logbook documentation and a building plan showing every device, cable route and network schematic, ready for your golden thread records.
