With a traditional extractor fan, you switch it on when it’s needed most (e.g. in a  steamy bathroom or smoky kitchen) and the fan expels the dirty or humid air. It’s effective, but it’s not designed to ventilate a building; merely to expel smelly or damp air. It’s noisy. It typically has a limited lifespan, because any motor required to work that hard that often will usually wear out after a few years (consider how many times in the past 20 years you’ve replaced or repaired your cooker hood). And it’s an expensive option, because a fan working at top speed is always going to be energy intensive.

But what if there was another way of doing it?

What is a continuous ventilation system?

A mechanical extraction ventilation (MEV) system uses either a single fan or several to deliver a steady, gentle flow of air through a space, extracting stale air and replacing it with clean air.

How do continuous extractor fans work?

A continuous ventilation system (as the name suggests) is always on. It relies on trickle vents (of the sort you’ll usually find at the top of UPVC windows) to provide a steady intake of air, while a continuously running extractor fan removes excess moisture and odours.

The flow of air is created by the fan and trickle vents operating in tandem. The fan expels air, creating marginally lower pressure in the building and encouraging air to flow through the trickle vents to achieve equilibrium.

Your continuous ventilation system could be centralised or decentralised. With a centralised system, a single continuous ventilation fan serves the whole building. You’ll often find this sort of system in new builds because, for it to work effectively, the system needs ducting to ensure expelled air finds its way to the fan. It’s usually easier to install that ducting when the building is under construction.

A decentralised system uses a ventilation fan in each room to achieve the same result while avoiding the need to install ducting throughout the building, which may be costly or impractical.

Benefits of continuous running extractor fans

1.     Cost savings

Despite the fact that it’s always on, continuous extract ventilation usually delivers energy savings compared to traditional intermittent extractor fans because the fan never operates at anything other than a low rate.

2.     Ventilation and extraction

The problem with extractor fans is that they only extract. They’re not designed to ventilate, that is, provide a constant supply of fresh air to a space, because they don’t run constantly.

A continuous ventilation fan system extracts the damp, smelly air you don’t want. There’s often even a booster to increase fan speed when you’ve burnt the toast. But an MEV also helps to replace that dirty air by gently pulling fresh air through the home via its trickle vents.

That’s especially good news for anyone who suffers from dust or pet allergies, as the flow of air helps to minimise the effects. But improving indoor air quality can also benefit quality of sleep and overall wellbeing.

3.     Low noise

If your bathroom extractor clicks into life every time someone turns the light on, you’ll be familiar with the experience of lying and waiting for it to switch off again so that peace can return.

Continuous extract ventilation is usually whisper quiet, so you get the full effect of an extractor fan without 15 minutes of noise every time someone switches it on.

4.     Unobtrusive

You’ll hardly ever notice a centralised system. But even with a decentralised system, continuous ventilation fans are discreet and unobtrusive.

5.     Easy to install and maintain

If you were building a home from scratch, a centralised continuous ventilation system would be the way to go. It wouldn’t usually be practical (or simple) to install such a system in an existing home.

A decentralised MEV, however, is simple to install, works perfectly effectively in older buildings, and needs minimal maintenance.

Install a system now and discover the difference it can make to your allergies, to your quality of sleep, and to your general health.

Why Green Improve?

Because we match real expertise with the very best products. If you’d like to explore options for a centralised or decentralised continuous ventilation fan system, talk to us.