Home ventilation, County Londonderry
Continuous extract fans (dMEV) in County Londonderry
Quiet low-energy fans that run all the time and boost automatically when humidity rises, across County Londonderry.
- From £315 inc VAT per fan
- By arrangement
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.
Our team is based in Great Barr, Birmingham, and we work throughout County Londonderry, from Coleraine, Limavady and Derry. Work here is by arrangement, with travel quoted in writing first.
dMEV fans in County Londonderry at a glance
- Area
- County Londonderry, Northern Ireland
- Towns listed
- 3, largest Derry
- Postcode districts
- BT48, BT52, BT55, BT49 and BT47
- Price region
- Northern Ireland
- Survey
- By arrangement, travel quoted first
What the work involves
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.
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.
Bathroom and en-suite
Through-wall or ceiling fans with humidity-controlled boost.
Guide prices in County Londonderry
| Work | Guide price |
|---|---|
| Continuous-running extract fan (dMEV) with humidity boost, flow tested (per fan) | £315–£550 inc VAT |
| Airflow testing and commissioning sheet for extract fans (up to 6 fans) (per home) | £135–£270 inc VAT |
These ranges use our Northern Ireland rates. Prices include VAT at 20%. You get a fixed written price before any work is booked. Travel is quoted separately for this area.
Signs it is time to call us
- Mould keeps returning in a bathroom with a working fan
- You manage rental homes and want ventilation that cannot be switched off
- You are refurbishing several wet rooms at once
Rules in Northern Ireland
Northern Ireland has its own building regulations, with ventilation guidance in Technical Booklet K. Extract rates follow the Northern Ireland guidance and are measured at handover.
How the job runs
- Survey
- Specify
- Fit
- Commission
- Record
Towns we cover in County Londonderry
Questions about continuous extract fans (dMEV) in County Londonderry
Are prices different in County Londonderry?
Our guide prices are adjusted by region. In County Londonderry we use Northern Ireland rates, so continuous-running extract fan (dMEV) with humidity boost, flow tested is typically £315 to £550 inc VAT per fan.
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.
Is it expensive to run a fan all the time?
No. dMEV fans use very little electricity on trickle speed, typically a few watts, so running costs are low compared with the condensation and mould they prevent.
Is the survey free in County Londonderry?
Visits here are by arrangement. Because of the ferry or long travel involved, we quote travel separately and in writing before you commit, and we can often combine visits to keep the cost down.
Which rules apply to ventilation in County Londonderry?
In Northern Ireland, ventilation is covered by Technical Booklet K of the Building Regulations (Northern Ireland). Workplaces must be ventilated under the Workplace (Health, Safety and Welfare) Regulations (Northern Ireland) 1993.
Other services in County Londonderry
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.