Home ventilation, Cornwall
Continuous extract fans (dMEV) in Cornwall
Quiet low-energy fans that run all the time and boost automatically when humidity rises, across Cornwall.
- From £360 inc VAT per fan
- Free survey
A dMEV (decentralised mechanical extract ventilation) fan is a low-energy extract fan that runs continuously at a quiet trickle speed and boosts automatically when it senses humidity or a light switch. Because it never fully switches off, moisture is removed steadily instead of building up between showers.
Every job in Cornwall gets a written quote before it starts and a commissioning record when it finishes. We cover Redruth, Falmouth, St Austell, Truro and Camborne and the villages around them.
dMEV fans in Cornwall at a glance
- Area
- Cornwall
- Towns listed
- 10, largest Redruth
- Postcode districts
- TR14, TR15, TR7, TR8, TR17 and TR18
- Price region
- South West
- Survey
- Free survey (UK mainland)
What continuous extract fans (dMEV) involves
Landlords and housing associations often choose them because tenants cannot switch them off and forget them. Under Approved Document F, continuous mechanical extract systems need commissioning: the airflow on both trickle and boost is measured and recorded. We do that as part of the job, so you have a record for building control, a landlord file or a future buyer.
Kitchen
Higher-rated continuous fans where a ducted hood is not practical.
Whole-home dMEV upgrade
Every wet room converted at once, with trickle vents checked in the habitable rooms.
Commissioned and recorded
Trickle and boost rates measured and written on a commissioning sheet.
Guide prices in Cornwall
| Work | Guide price |
|---|---|
| Continuous-running extract fan (dMEV) with humidity boost, flow tested (per fan) | £360–£625 inc VAT |
| Airflow testing and commissioning sheet for extract fans (up to 6 fans) (per home) | £150–£305 inc VAT |
Guide prices using South West rates. Prices include VAT at 20%. A guide price is not a quote: we confirm a fixed price in writing first.
Common reasons people call
- Occupants switch fans off because of noise
- Mould keeps returning in a bathroom with a working fan
- You manage rental homes and want ventilation that cannot be switched off
Rules in 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.
How the job runs
- Survey
- Specify
- Fit
- Commission
- Record
Towns we cover in Cornwall
Questions about continuous extract fans (dMEV) in Cornwall
Which towns in Cornwall do you cover?
All of Cornwall, including Redruth, Falmouth, St Austell, Truro and Camborne. If your town is not listed, send the postcode and we will confirm.
Can dMEV fans be fitted where a fan already exists?
Usually yes. Most fit the existing hole or duct, which keeps the cost and mess down.
How much does a continuous extract fan cost?
A dMEV fan usually costs £345 to £595 including VAT per room, supplied, fitted and commissioned. Converting several rooms in one visit brings the cost per fan down.
Are prices different in Cornwall?
Our guide prices are adjusted by region. In Cornwall we use South West rates, so continuous-running extract fan (dMEV) with humidity boost, flow tested is typically £360 to £625 inc VAT per fan.
Is the survey free in Cornwall?
For new installations on the UK mainland, yes. The survey is free and the quote that follows is fixed and in writing. Servicing, testing and repair visits are charged, and we confirm the cost before booking.
Other services in Cornwall
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.