An opening window is not enough on its own in most bathrooms, especially in winter when nobody opens it. Moisture from a shower settles on the coldest surfaces first: the ceiling, the window reveal, the corner behind the WC. Over time that means black mould in the grout and silicone, flaking paint and swollen furniture. A fan that is sized and ducted properly, and keeps running long enough after each shower, stops most of it.
Supplying and fitting a standard extractor fan with a timer or humidistat, ducted outside and wired to regulations, typically costs £250 to £450 including VAT. A quieter inline fan in the loft with a ceiling grille costs £400 to £700, and a low-energy continuous extract fan that runs all the time and boosts on humidity £450 to £900. Most fans are fitted in half a day.
What does a bathroom extractor fan with us include?
- A check of the room, any existing fan or vent, and the shortest route to the outside
- A fan chosen to meet the bathroom extract rate: 15 l/s intermittent or 8 l/s continuous
- Core-drilling through the wall, or ducting through the loft to a roof or soffit vent
- Rigid or semi-rigid ducting kept short and straight, and insulated where it crosses a cold loft
- A backdraught shutter and external grille, so cold air does not blow back in
- Wiring by a qualified electrician, with an isolator outside the room and RCD protection
- Run-on timer, humidistat or light-linked switching set up to suit how the room is used
- Making good around the fan and checking that it extracts properly at the grille
How much does a bathroom extractor fan cost?
Our UK guide range is £250–£600 including VAT. Typical prices by kind of job:
Extractor fan
- Fan with timer or humidistat
- Ducted to outside
- Wired to regulations
Inline fan
- Quiet fan in the loft void
- Ducting to a roof or soffit vent
- Grille in the ceiling
Continuous extract
- Low-energy fan running all the time
- Boost on humidity
- Good for windowless rooms
National guide prices including VAT, reviewed October 2026. London is typically about 25% higher and the North East, Wales and Northern Ireland around 7–12% lower. Your written quote after the survey is the price that counts.
What do you need to decide?
Wall or ceiling
A wall fan on an outside wall is the simplest. A ceiling fan over the shower takes steam away at source but needs ducting through the loft.
Axial, centrifugal or inline
Axial fans suit short, straight runs; centrifugal fans cope better with longer ducts; inline fans sit in the loft and are the quietest in the room.
Timer or humidistat
A timer keeps the fan running after the light goes off. A humidistat starts it whenever moisture rises, which suits rooms where people forget.
Intermittent or continuous
An intermittent fan runs during and after use. A continuous fan runs quietly all the time at a low rate and boosts when humidity rises.
Replacement air
A fan needs air to replace what it removes, so leave a gap of around 10 mm under the door or fit a door grille. A sealed room starves the fan.
Noise
Compare the stated noise level in decibels. Inline fans and low-speed continuous fans are much quieter in the room than budget axial fans.
