A retrofit may be required because the building has no automatic smoke ventilation, the original system has become obsolete or alterations have changed the building’s fire-safety requirements.

Nevertheless, existing buildings can present challenges that are not normally found in new developments. These may include restricted cable routes, unsuitable windows, limited roof access, occupied areas and missing design information.

At

AK Fire Safety
,
we provide professional

AOV surveys, retrofits, installations, upgrades and repairs

throughout the United Kingdom.

Why Retrofit an AOV System?

The AOV Retrofit Process

Can Existing Windows Be Converted into AOVs?

An existing window may sometimes be converted by installing a suitable electric actuator and connecting it to an AOV control panel.

However, the window should be assessed for:

• Frame condition
• Hinge condition
• Window size and weight
• Opening direction
• Required opening angle
• Geometric or aerodynamic free area
• Suitable actuator mounting points
• Wind loading
• Weather exposure
• Security and fall-protection risks
• Compatibility with the smoke-control design

Can Existing Rooflights Be Upgraded?

Some rooflights can be fitted with new actuators or replaced with purpose-designed natural smoke and heat exhaust ventilators.

The survey should examine:

• The rooflight frame and glazing
• The condition of hinges and seals
• The roof kerb
• Opening dimensions
• Drainage and weatherproofing
• Actuator compatibility
• Roof access
• Wind and snow exposure
• Required certification

Where the existing rooflight is damaged, poorly insulated or unsuitable, complete replacement may offer better long-term value.

Can an Existing Smoke Shaft Be Reused?

An existing smoke shaft may sometimes be retained and fitted with upgraded dampers, controls or mechanical extraction.

However, the assessment should confirm:

• The shaft dimensions
• The shaft construction and condition
• Fire and smoke resistance
• The condition of floor dampers
• Access for inspection and maintenance
• The condition of the shaft-head vent
• Whether mechanical extraction is proposed
• Replacement-air arrangements
• The required airflow performance

If the building layout has changed, the original shaft design may need to be reassessed rather than automatically reused.

Can an Old AOV Panel Be Replaced?

Yes. Replacing an obsolete or unreliable AOV control panel is one of the most common smoke-control upgrades.

Nevertheless, panel replacement is not always a direct exchange. The contractor should check:

• The operating voltage of existing actuators
• The total current and load requirements
• The number of smoke-control zones
• Existing circuit-monitoring arrangements
• Fire alarm interface types
• Manual control compatibility
• Standby battery capacity
• Existing cable condition
• Cause-and-effect programming
• Required fault and status outputs

Read our guide:

What Is an AOV Control Panel and How Does It Work?

Can Existing AOV Actuators Be Reused?

Existing actuators may be retained where they are compatible, supported and in suitable condition.

Engineers should check:

• Manufacturer and model
• Operating voltage
• Current requirements
• Opening force
• Stroke or chain length
• Bracket condition
• Cable condition
• Environmental rating
• Full opening and closing operation
• Compatibility with the replacement panel

An actuator that moves during a brief test may still be unreliable under load. Therefore, the complete vent should be functionally tested.

Can Existing Cabling Be Reused?

Existing cabling may sometimes be reused, although it should first be inspected and tested.

The assessment may consider:

• Cable type
• Fire-resistance requirements
• Conductor size
• Voltage drop
• Insulation condition
• Mechanical damage
• Cable support
• Existing joints
• Labelling
• Compatibility with circuit monitoring

Reusing unsuitable wiring to reduce cost can cause actuator faults, excessive voltage drop or unreliable monitoring.

Can a Retrofitted AOV Connect to the Fire Alarm?

Yes. A retrofitted AOV system can normally receive activation signals from a suitable fire alarm interface.

The interface may use:

• An addressable input/output module
• A monitored relay
• A volt-free contact
• A dedicated smoke-control interface
• Separate signals for individual floors

The existing fire alarm panel must have suitable capacity and compatible output options. Programming should also follow the approved cause-and-effect schedule.

Read:

Can AOV Systems Be Connected to a Fire Alarm?

Can Wireless Controls Be Used for an AOV Retrofit?

Wireless equipment may be available for certain inputs, monitoring functions or specialist applications. However, wireless technology should not be selected simply because installing cables is difficult.

The designer should consider:

• Product certification
• Signal reliability
• Battery monitoring
• Building construction
• Radio interference
• Required fault supervision
• Maintenance requirements
• Compatibility with the approved smoke-control design

High-current actuators and mechanical extract equipment will still require appropriate power and control arrangements.

Can AOV Systems Be Retrofitted into Apartment Buildings?

Yes. Apartment blocks are common candidates for AOV retrofits and upgrades, especially where communal corridors, lobbies or stairways need improved smoke control.

A residential retrofit may include:

• Automatic corridor windows
• A stair-head roof vent
• Natural smoke-shaft dampers
• Mechanical smoke extraction
• Replacement-air openings
• Dedicated smoke detectors
• Communal fire alarm interfaces
• Firefighter controls

Work should be planned carefully to minimise disruption to residents and keep escape routes available.

Read our related guide:

Do Apartment Buildings Need AOV Systems?

Can AOVs Be Retrofitted into Listed Buildings?

It may be possible to install smoke-control equipment in a listed or heritage building. However, additional permissions and a sensitive design may be required.

Possible considerations include:

• Listed-building consent
• Planning requirements
• Protected windows and roof features
• Concealed cable routes
• Visual impact
• Reversible installation methods
• Coordination with conservation specialists
• Bespoke equipment finishes

Fire-safety requirements and heritage protection should be considered together from the beginning of the project.

Can the Building Remain Occupied During Retrofit Work?

Many AOV retrofits can be completed while a building remains occupied. Nevertheless, the responsible person and contractor must manage temporary impairments carefully.

Suitable controls may include:

• Phased installation
• Working on one zone at a time
• Resident or employee notifications
• Controlled system isolations
• Daily restoration checks
• Temporary fire-safety measures
• Keeping escape routes clear
• Out-of-hours working
• Coordinating fire alarm testing

Common Challenges When Retrofitting AOV Systems

What Should an AOV Retrofit Survey Include?

Repair, Partial Upgrade or Complete Replacement?

A professional assessment may recommend repair, partial upgrading or full replacement.

How Much Does an AOV Retrofit Cost?

The cost depends on the amount of equipment that can be reused and the level of building work required.

Factors include:

• Number of smoke-control zones
• Number and size of vents
• Actuator type
• Control-panel capacity
• Fire alarm integration
• New cable routes
• Roof and high-level access
• Structural alterations
• Making good
• Commissioning requirements

Read our pricing guide:

How Much Does an AOV System Cost?

Does a Retrofitted AOV Need Commissioning?

Yes. A retrofit or upgrade should be fully commissioned before it is returned to service.

Commissioning should confirm:

• The correct detectors and interfaces activate.
• The correct smoke-control zone operates.
• Windows and roof vents reach their required positions.
• Smoke-shaft dampers operate correctly.
• Unaffected dampers remain closed where required.
• Mechanical extract fans start.
• Replacement-air openings operate.
• Standby batteries support the system.
• Fault monitoring works.
• Manual firefighter controls operate.
• The reset sequence is correct.

Testing only the new control panel does not prove that retained vents, wiring or actuators operate correctly.

What Documentation Should Be Updated?

Retrofit work should be recorded so that future contractors and building managers understand the new system.

Updated documentation may include:

• Smoke-control drawings
• Cause-and-effect schedule
• Control-panel zone information
• Fire alarm interface details
• Equipment asset lists
• Battery and power calculations
• Commissioning records
• Operating instructions
• Maintenance requirements
• Details of retained equipment
• Details of removed or isolated equipment

What Standards Apply to AOV Retrofit Work?

The applicable standards depend on the system type, building and scope of work. Relevant documents may include:

• BS 7346-8 – recommendations for planning, design, installation, commissioning and maintenance of smoke-control systems.
• BS EN 12101-2 – natural smoke and heat exhaust ventilators.
• BS EN 12101-3 – powered smoke and heat-control ventilators.
• BS EN 12101-7 – smoke duct sections.
• BS EN 12101-8 – smoke-control dampers.
• BS EN 12101-10 – smoke-control power supplies.
• Approved Document B – fire-safety guidance supporting the Building Regulations in England.
• The current building fire strategy.
• The equipment manufacturers’ instructions.

BSI describes

BS 7346-8

as providing recommendations for natural and mechanical smoke-control systems.

Information about the wider

BS EN 12101 smoke and heat-control series

is available from BSI.

Current government guidance can be accessed through the

Approved Document B publication page
.

Who Is Responsible for a Retrofitted AOV?

Responsibility commonly rests with the building owner, landlord, employer, managing agent, housing provider or facilities manager acting as the responsible person.

They should ensure that:

• The work follows a suitable design.
• Competent contractors are appointed.
• Temporary impairments are managed.
• The completed system is commissioned.
• Documentation is updated.
• Building users receive suitable information.
• Ongoing maintenance is arranged.
• Faults are repaired promptly.

Article 17 of the Regulatory Reform (Fire Safety) Order 2005 requires necessary fire-safety equipment to be suitably maintained and kept in efficient working order.

Read

Article 17 of the Fire Safety Order
.

Frequently Asked Questions

Professional AOV Retrofit Services

AK Fire Safety provides professional AOV retrofit, upgrade, repair and recommissioning services for existing buildings.

Our services include:

• AOV retrofit surveys
• Existing-system condition assessments
• Control-panel replacement
• Actuator replacement and upgrades
• Automatic window conversions
• Roof-vent replacement
• Smoke-shaft damper upgrades
• Fire alarm interface installation
• Standby battery replacement
• Cable and circuit assessments
• Cause-and-effect programming
• Mechanical smoke-extract integration
• Complete system commissioning
• Updated system documentation
• Planned preventative maintenance
• Nationwide multi-site support

Conclusion

AOV systems can often be retrofitted into existing buildings. Existing windows, rooflights, smoke shafts and some actuators may sometimes be retained or upgraded.

However, the project should begin with a professional survey and review of the building’s fire strategy. This confirms what the system needs to achieve and which existing components remain suitable.

The retrofit may require new control panels, standby batteries, actuators, smoke detectors, fire alarm interfaces, cabling, dampers or extract equipment.

Most importantly, the completed installation should be fully commissioned. Testing should begin at the initiating device and finish by confirming that every required vent, damper, fan and replacement-air opening operates correctly.