What to Know Before Choosing Smoke Vents for Your Build

Smoke vents aren’t just a nice-to-have feature. In the event of a fire, they can be the difference between a controlled situation and a catastrophe. They help to clear smoke, reduce heat build-up, and create safer evacuation routes. However, here’s the catch: not all smoke vent systems are equal, and choosing the wrong type – or placing them incorrectly – can undermine everything they are designed to do.

Before committing to anything, you need to get clear on a few things. Let’s walk through what really matters when it comes to selecting smoke vents for your project.

First, get clear on the purpose

Not all vents are installed for the same reason. So the first step is to understand exactly why you’re including them in your design.

There are two main reasons for using smoke vents:

• Life safety – to give occupants time to escape, reduce smoke inhalation risks, and make it easier for firefighters to enter.
• Property protection – to limit smoke and heat damage by clearing them efficiently and maintaining visibility for suppression systems.

Some projects require both, but how you approach the design and spec will change depending on the primary purpose. This needs to be agreed on early. If you guess or generalise here, it can cause delays or force revisions later down the line.

The difference between natural and mechanical smoke vents

There are two core types of smoke ventilation: natural and mechanical.

Natural smoke vents rely on buoyancy. As hot smoke rises, it escapes through openings at high levels in the building, usually the roof. Cooler air is drawn in from low-level inlets, creating a flow. No fans, no motors, just physics.

Mechanical smoke systems actively extract smoke using powered fans. They offer more control and are often used in spaces with limited natural airflow or where vent placement is restricted.

Each has its own pros and limitations. Natural systems are simpler, with fewer moving parts. Mechanical systems are more complex but can be more precise. Your choice will often depend on the shape of the building, its size, and how smoke is likely to behave in a fire scenario.

Look at the building layout

Some buildings are straightforward. Others are more of a maze. Multi-storey buildings, long corridors, or deep basements all create their own challenges when it comes to managing smoke.

It’s not just about how tall the building is. Think about:

• Ceiling heights
• Openings between floors
• Atriums or voids
• Compartmentation
• Escape routes

Where will smoke accumulate? How will it move through the space? Are there areas where people could become trapped?

This is where fire strategy comes into play. You need to consider how the vents interact with the entire fire safety plan, not just in isolation. Surespan smoke vents are one part of the system. They need to work in conjunction with fire doors, alarms, sprinklers, and escape signage.

Location matters more than you think

Even the best vent won’t work properly if it’s in the wrong place. A lot of buildings make the mistake of just “adding vents” without a proper flow strategy. That’s a risk.

For example, if an opening is placed too far from the fire source or escape route, it might not create the pressure difference needed to move the smoke efficiently. On the other hand, if they’re too close to walls or beams, airflow can be blocked.

Generally, you want smoke vents at the highest point of a space, with a clear vertical path for smoke to rise. Low-level air inlets should be positioned so they don’t interfere with escape routes or pull smoke back into occupied zones.

There’s no single layout that works for every project. What matters is that the positioning supports natural smoke movement and complements the building’s usage.

Don’t forget compliance

This isn’t just a technical decision – it’s a legal one. Smoke vents must meet strict building regulations and fire codes. This varies depending on the building type, size, and intended use.

You’ll need to check for things like:

• Automatic opening requirements – does it need to activate with a fire alarm?
• Fail-safe features – what happens in the event of power loss?
• Minimum vent area – based on floor size or compartmentation
• Test certification – is the product tested to the relevant standards?

Missing even one of these could result in failed inspections, redesigns, or worse, non-compliance that leaves you liable in the event of an incident. It’s not something to cut corners on.

Think about maintenance from day one

Here’s what gets overlooked: a smoke vent system isn’t install-and-forget. It needs regular testing and servicing to stay operational. That means easy access is key.

If a vent is stuck behind a hard-to-reach ceiling void or requires a full scaffold just to inspect, maintenance becomes a nightmare. Worse still, it might not get done at all.

Choose systems that are designed for long-term reliability, with clear access paths and simple maintenance routines. Ask how often they need to be serviced and what checks are required. This will save a lot of time, hassle, and cost later on.

Integration with other systems

Smoke vents don’t work in isolation. In a real fire, they need to interact with the rest of your safety systems in the right sequence.

Will they be triggered by a fire alarm? Does the system need to open fire doors at the same time? Will sprinklers affect the flow of smoke?

Think about the full chain of events:

1. A fire breaks out.
2. The alarm activates.
3. Smoke detection signals the control panel.
4. Smoke vents open (automatically or manually).
5. Air inlets respond to maintain pressure balance.

All of this needs to happen fast, and it needs to work the first time. Poor integration can cause delays or lead to systems working against each other.

Make the right choice early

Smoke vent systems aren’t something to tack on at the end of a build. They need to be considered early in the design process, alongside fire strategy, structural layout, and M&E planning.

When chosen carefully, smoke vents can do more than meet a regulation; they can save lives and protect property. So it’s worth putting in the effort to get them right from the start.