Continuous extract fans (dMEV)
Quiet low-energy fans that run all the time and boost automatically when humidity rises.
From £345 inc VAT per fan
Home ventilation
Extractor fan installation for bathrooms, kitchens and utilities
Bathroom, kitchen and utility fans sized to the Part F rates, ducted outside and tested.
- From £175 inc VAT per fan
- Free survey on the UK mainland
- Airflow tested and recorded
An extractor fan removes steam and smells at the point they are made, before they spread through the house and settle as condensation. We fit new fans, replace failed ones, and re-route ducts that blow into the loft instead of outside, choosing a fan that can actually move the airflow the room needs.
How it works
Many existing fans were never doing their job: undersized, ducted into the loft space, fitted with a flex duct crushed in the joists, or switched off by occupants because they were noisy. The rate a fan delivers through a real duct run is often far lower than the number on the box, which is why we size to the room and test the result.
For England, Approved Document F gives minimum intermittent extract rates: 15 litres a second for a bathroom, 30 for a kitchen with a cooker hood (60 without one), 30 for a utility room and 6 for a WC. Wales, Scotland and Northern Ireland have their own rules, which we follow where the job is.
Options we fit
Like-for-like replacement
A new fan on the existing duct and wiring, often with an overrun timer or humidity sensor.
New fan through an outside wall
Core drilled, sleeved, wired from a fused spur and sealed outside.
Ducted to outside through the loft
Insulated duct to a roof, ridge or soffit outlet so warm moist air does not condense in the loft.
Inline fans
A quiet fan in the loft serving one or two ceiling grilles in a shower room or en-suite.
Kitchen extract and cooker hoods
A wall or window fan, or a cooker hood ducted outside rather than recirculating.
Signs you need this
- Mirror still steamed up 20 minutes after a shower
- Mould on the bathroom ceiling or around the window
- The fan runs but a sheet of toilet paper does not stick to the grille
- The fan is noisy, rattling or has stopped
- The duct ends in the loft rather than outside
- A kitchen with a recirculating hood and condensation on the windows
Guide prices
| Work | Guide price |
|---|---|
| Like-for-like extractor fan replacement (existing duct and wiring) (per fan) | £175–£295 inc VAT |
| New extractor fan through an outside wall (core drilled, wired, tested) (per fan) | £345–£545 inc VAT |
| New ducted fan to outside through the loft or ceiling (insulated duct, roof or soffit outlet) (per fan) | £445–£745 inc VAT |
| Inline fan for a shower room or en-suite (loft-mounted, one or two ceiling grilles) (per room) | £545–£895 inc VAT |
| Kitchen extract fan, or cooker hood ducted to outside (per kitchen) | £395–£695 inc VAT |
Guide prices using West Midlands (our baseline) rates. Home prices include VAT at 20%; business prices exclude VAT. A guide price is not a quote: we confirm a fixed price in writing first. London is about 20% higher and the North East about 8% lower.
What happens, step by step
Quick survey
We check the room, the existing duct route and where the wiring can come from.
Choose the fan
Sized to the room and duct length, with a timer, humidistat or continuous low speed where it helps.
Fit and duct
Core drill or duct route, outlet sealed outside, fan fixed and grille fitted.
Wire
Connected to the lighting circuit or a fused spur to the current wiring regulations.
Test
Airflow measured at the grille and the result written down for you.
The rules that apply
England
In England, ventilation is covered by Part F of the Building Regulations and its guidance, Approved Document F (2021 edition). For homes, it sets minimum extract rates such as 15 litres a second for a bathroom and 30 or 60 for a kitchen, and expects mechanical systems to be airflow-tested.
Wales
Wales has its own Part F ventilation guidance, published by the Welsh Government, and work is checked by building control. We design to the Welsh rates and commission mechanical systems so the results can be recorded.
Scotland
In Scotland, ventilation is covered by the Building (Scotland) Regulations and section 3 of the Technical Handbooks, and most building work needs a building warrant first. We work to the Scottish ventilation standards and record the airflow achieved.
Northern Ireland
In Northern Ireland, ventilation is covered by the Building Regulations (Northern Ireland) and Technical Booklet K. We design to the Northern Ireland guidance and measure the airflow achieved.
Questions people ask
How much does it cost to fit an extractor fan?
Replacing a fan on an existing duct usually costs £175 to £295 including VAT. A new fan through an outside wall is typically £345 to £545, and a fan ducted to outside through the loft £445 to £745.
What size extractor fan does a bathroom need?
In England a bathroom fan should extract at least 15 litres a second, measured at the fan, under Approved Document F. Long or bendy duct runs reduce flow, so the fan often needs to be rated higher than the minimum.
Can an extractor fan vent into the loft?
No. A fan should discharge to outside, because warm, moist air dumped in the loft condenses on the cold roof timbers and causes mould and rot there instead.
Should I get a fan with a humidity sensor?
A humidistat fan switches on when the air gets damp and runs until it clears, which suits family bathrooms and rentals where people forget the switch. A continuous-running fan is another good option.
Do you need building regulations for a new extractor fan?
Fitting or replacing an extractor fan has to meet the ventilation and electrical rules, and certain electrical work is notifiable. We do the work to the current standards. Electrical work that is notifiable is certified by a registered electrician, and you get a copy of the certificate and our airflow readings.
How long does fitting a fan take?
A straight replacement takes an hour or two. A new fan with a core-drilled hole or a duct through the loft usually takes half a day.
Related services
Positive input ventilation (PIV)
Loft or wall units that gently push filtered air into the home to tackle condensation.
From £795 inc VAT per home
Condensation and mould ventilation fixes
We find why the house is wet and fix the ventilation, rather than painting over mould.
From £445 inc VAT per fan
Ventilation repairs and fault finding
Noisy, failed or leaking fans, PIV, MVHR and commercial extract put right.
From £95 inc VAT per visit
Read before you buy
Extractor fan installation by area
Choose your area for local guide prices and the towns we cover.
- Bedfordshire
- Berkshire
- Bristol
- Buckinghamshire
- Cambridgeshire
- Cheshire
- Cornwall
- Cumbria
- Derbyshire
- Devon
- Dorset
- County Durham
- East Riding of Yorkshire
- East Sussex
- Essex
- Gloucestershire
- Greater London
- Greater Manchester
- Hampshire
- Herefordshire
- Hertfordshire
- Isle of Wight
- Kent
- Lancashire
- Leicestershire
- Lincolnshire
- Merseyside
- Norfolk
- North Yorkshire
- Northamptonshire
- Northumberland
- Nottinghamshire
- Oxfordshire
- Rutland
- Shropshire
- Somerset
- South Yorkshire
- Staffordshire
- Suffolk
- Surrey
- Tyne and Wear
- Warwickshire
- West Midlands
- West Sussex
- West Yorkshire
- Wiltshire
- Worcestershire
- Clwyd
- Dyfed
- Gwent
- Gwynedd and Anglesey
- Mid Glamorgan
- Powys
- South Glamorgan
- West Glamorgan
- Edinburgh
- Lothians
- Glasgow
- Lanarkshire
- Renfrewshire and Inverclyde
- Dunbartonshire
- Ayrshire
- Fife
- Forth Valley
- Tayside
- Aberdeen and Aberdeenshire
- Highland and Moray
- Dumfries and Galloway
- Scottish Borders
- Argyll and Bute
- Scottish Islands
- County Antrim
- County Armagh
- County Down
- County Fermanagh
- County Londonderry
- County Tyrone
Get a guide price in two minutes
Answer a few questions for a price range, or send photos and we will come back to you with a written quote.