Condensation and mould ventilation fixes in County Londonderry

In County Londonderry homes, black mould usually comes down to the same few causes: weak fans, loft-vented ducts and no background ventilation.

We carry out condensation and mould ventilation fixes across County Londonderry, including Coleraine, Limavady and Derry. Prices use Northern Ireland rates. Work here is by arrangement, with travel quoted in writing first.

Condensation & mould in County Londonderry at a glance

Area: County Londonderry, Northern Ireland
Towns listed: 3, largest Derry
Postcode districts: BT49, BT47, BT48, BT52 and BT55
Price region: Northern Ireland
Survey: By arrangement, travel quoted first

What the work involves

A typical family puts several litres of water into the air every day. If extract fans are weak, ducted into the loft or switched off, and windows stay shut in winter, that moisture settles on the coldest surfaces: window reveals, external corners, behind wardrobes and on bathroom ceilings. Mould needs that damp surface to grow.

Fan upgrades

Weak or loft-vented fans replaced and ducted outside, with humidity control.

Whole-home ventilation

PIV, continuous extract or MVHR where moisture is spread through the house.

Mould treatment advice

How to clean and treat affected areas once the cause is fixed.

Guide prices in County Londonderry

Condensation and mould ventilation fixes guide prices in County Londonderry
Work	Guide price
New ducted fan to outside through the loft or ceiling (insulated duct, roof or soffit outlet) (per fan)	£410–£675 inc VAT
Positive input ventilation (PIV) loft unit, supplied and fitted (per home)	£725–£1,275 inc VAT
Continuous-running extract fan (dMEV) with humidity boost, flow tested (per fan)	£315–£550 inc VAT
Condensation and mould ventilation survey with written findings (per home)	£115–£205 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.

Common reasons people call

Black mould on window reveals, ceilings or behind furniture
Water running down windows on cold mornings
Musty smell in bedrooms or wardrobes

Rules in Northern Ireland

Northern Ireland has its own building regulations, with ventilation guidance in Technical Booklet K. Landlords in Northern Ireland have repairing and fitness obligations that cover serious damp.

How the job runs

Survey
Find the cause
Recommend
Fix
Check back

Towns we cover in County Londonderry

Questions about condensation and mould ventilation fixes in County Londonderry

Which towns in County Londonderry do you cover?

All of County Londonderry, including Coleraine, Limavady and Derry. If your town is not listed, send the postcode and we will confirm.

How much does a condensation survey cost?

A ventilation survey with written findings costs £125 to £225 including VAT.

Can you tell if it is rising damp?

We can tell you when the pattern does not look like condensation, such as a tide mark low on a wall or damp that appears after rain, and point you to the right specialist.

Are prices different in County Londonderry?

Our guide prices are adjusted by region. In County Londonderry we use Northern Ireland rates, so new ducted fan to outside through the loft or ceiling (insulated duct, roof or soffit outlet) is typically £410 to £675 inc VAT per fan.

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.

Send us photos of the mould and your fans and we will give a first view for your County Londonderry home.