What does a bathroom extractor fan cost in Dorset?
Our guide range in Dorset is £255–£600 including VAT.
Extractor fan
- Wired to regulations
Inline fan
- Quiet fan in the loft void
Continuous extract
- Boost on humidity
Guide prices for Dorset including VAT. Your itemised written quote after the free survey is the price that counts.
Which towns do we cover in Dorset?
Most of Dorset has hard water. Steam carries that scale onto mirrors and glass, so a fan that clears the room quickly helps on both counts. Hardness varies street by street, so check the figure for your postcode with your water supplier. We check the duct route at Bournemouth surveys, because a short, straight run to outside matters more than the fan's headline figure.
What the job includes
- A backdraught shutter and external grille, so cold air does not blow back in
- 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
- Making good around the fan and checking that it extracts properly at the grille
Decisions to make first
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.
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.
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.
Rules that apply in England
A bathroom needs extract ventilation when it is newly formed, and on a refit an existing fan should not be replaced with a less effective one. The fan and its wiring must meet BS 7671 for the zone it sits in, on a circuit with 30 mA RCD protection. In a flat, the lease often requires freeholder consent for a new extract vent, and in a listed building a new opening through an external wall can need listed building consent.
In England, Approved Document F sets bathroom extract at 15 l/s for an intermittent fan or 8 l/s for continuous extract. Wiring a new fan alters a circuit in a room with a bath or shower, so it is notifiable under Part P.