The Function of Smoke Vents

Smoke vents are fitted into the roof of a building as part of the fire safety system. They are usually used within commercial buildings where there is a large volume of people, though they are also often used in blocks of flats. They are essentially a rooflight that is fitted into the roof of a building, but that is able to open to become a vent for smoke removal in the case of a fire.

You may also hear smoke vents being called SHEVs. This stands for smoke and heat exhaust ventilation, which refers to the function carried out by a smoke vent.

What do smoke vents actually do? 

Smoke vents and SHEVs are primarily designed to vent out smoke in the case of a fire. This is really important, as smoke is incredibly dangerous. In fact, it is a bigger killer than fire itself and most deaths that result from a fire are actually caused by smoke inhalation.

When a fire is detected, the vent will be opened, either manually or as part of the wider fire safety system. Automatic opening vents, or AOVs, can be wired up to the fire alarm system using control panels, so when the alarm is set off, the system will automatically open up the vent.

Why are smoke vents so beneficial? 

Smoke vents help to clear smoke, which is extremely important in the event of a fire. This helps to reduce the levels of smoke inside a building so that it is safer for the people inside. They will be breathing in less smoke and less toxic air. It also makes it easier for firemen and anyone else present at the scene of the fire, as with a reduced amount of smoke, there will be better visibility. This will help them to assist the people inside the building and to give a clearer escape route.

Smoke vents also have the added bonus of providing ventilation for a building. Vents that can be opened manually can be used to allow better air circulation, improving the quality of air inside the building on a day-to-day basis.

Why should smoke vents be installed? 

Smoke vents installed in any building will improve fire safety measures and will help reduce fatalities and casualties in the event of a fire. However, it may also be required for you to fit a smoke vent in order to comply with buildings regulations. You will be able to find the information you need in Building Regulation Approved Document B, which covers dwellings and non-dwellings and sets out requirements for ventilation systems. If you think you may need some form of ventilation in your property, consult buildings regulations as the first port of call.


AOVs, SHEVs and smoke vents have a very important function. There is lots of research that needs to be carried out for each individual situation, so look into their installation and find out which parts of fire safety legislation apply to you. It’s much better to be safe than sorry when it comes to fire safety.