Roof Windows

An AOV window (Automatic Opening Vent window) is a type of window designed to open automatically in response to smoke or fire, helping to ventilate a building and extract smoke. These windows are typically connected to a smoke control system and can be triggered by fire alarm systems, smoke detectors, or manual call points.

When smoke or heat is detected (by smoke detectors or manual call points), the AOV system triggers the actuators to open the windows. This opening creates ventilation, allowing smoke and heat to be expelled from the building. This helps to keep escape routes clear of smoke, allowing people to evacuate safely and providing access for firefighters. 

• Improved safety: AOVs help create safer evacuation routes during a fire. 
• Reduced fire damage: Efficient smoke and heat removal can help minimise fire damage. 
• Compliance with regulations: AOV systems are often required by building regulations to ensure adequate fire safety measures. 

You do not generally need planning permission for a roof window. It typically depends on the building and its use. You may need to obtain Building Regulations approval, which is separate from planning permission.

According to the UK Government’s Planning Portal, approval is typically required for installing a new roof window due to the following factors:

• Modifying the roof structure to create an opening.
• Ensuring the roof can support the weight of the window—additional reinforcement may be necessary.
• Meeting energy efficiency standards to prevent heat loss.
• Considering fire performance requirements if the window is near a boundary.

It is dependent on the installer, however, it can take between 1.5-4 hours of installation time.