How to Turn Your Extractor Fan into a Budget Air Purifier

In many kitchens, the extractor fan is treated as nothing more than a way to deal with steam and smoke from the hob. However, with a straightforward tweak, it can behave a bit like a basic air purifier, helping to cut down on cooking smells, airborne grease and smoke particles-without major work or high costs.

How can you turn an extractor fan into a low-cost air purifier?

The idea is to add an extra disposable filter layer over the grille or on top of the unit’s original metal filter. This takes advantage of the extractor fan’s suction, forcing air to pass through the additional mat, which then traps finer grease residue and some of the smoke.

In effect, the extractor fan starts working like a simple air-cleaning device: air is pulled in, pushed through the filter mat, and then returned to the room (or vented outside, depending on your setup) with fewer impurities. In small or poorly ventilated kitchens, people typically notice less lingering frying odour, reduced sootiness and a less stuffy feel.

You can watch a video on the YouTube channel Josenilson Facilita showing how to make a filter for a recirculating hood and cooker hood. The video demonstrates, in a practical way, how to use filter mats and charcoal filters to capture grease and smells while you cook.

What materials and steps are needed to adapt the extractor fan?

To do this safely, use materials intended for kitchens or ventilation-items designed to cope with moderate heat and grease. Below is a simple step-by-step method for fitting a filter mat without harming the appliance’s performance.

• Disposable filter mat made for an extractor fan, cooker hood or air conditioner
• Scissors or a craft knife to cut the material to size
• Heat-resistant adhesive tape or suitable clips to secure it
• Simple gloves to avoid direct contact with built-up grease

1. Switch off the extractor fan at the plug or consumer unit before handling anything.
2. Remove the grille or metal filter, following the manufacturer’s instructions.
3. Give the removed part a quick clean, taking off any visible grease.
4. Cut the filter mat to match the shape of the grille or original filter.
5. Attach the disposable filter over the metal surface, keeping it taut and flat.
6. Refit the grille or filter in the extractor fan, checking it sits securely.
7. Turn the unit back on and confirm the airflow is normal and there are no unusual noises.

What precautions keep it safe and effective for everyday use?

The key is not to restrict the airflow too much and not to use flammable materials such as cloths, kitchen roll or sponges. Ideally, choose filter mats designed for extractor fans, cooker hoods or ventilation systems, as they are made to tolerate heat and contact with grease without easily melting or catching fire.

Regular upkeep matters too, because the disposable filter will eventually become saturated. As it loads up with grease and dust, the motor has to work harder. In kitchens with heavy use, it is worth checking the mat every two weeks and replacing it, on average, every 30 days; with moderate use, replacement usually falls somewhere between 45 and 60 days.

When does the extractor fan trick make the biggest difference to air quality?

The improvement is generally most noticeable in compact flat kitchens, in homes without large windows near the hob, and in open-plan spaces that flow into a living room. In these situations, the adapted extractor fan helps limit strong smells drifting into sofas, curtains and clothing, making the post-cooking period less irritating.

Where fitting a powerful cooker hood or external ducting is not possible, this approach can act as a simple ventilation boost-especially for frying and grilling. When paired with some natural ventilation and routine cleaning of the fan blades, housing and air outlet, it can also help reduce grease settling on surfaces and keep the air more pleasant day to day.