Positive input ventilation (PIV) in County Londonderry

For a typical County Londonderry semi or terrace, a loft PIV unit is often the quickest way to dry the house out.

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.

PIV 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

Loft air is usually a little warmer and drier than outside air, and the unit filters it before it comes down into the house. Many units have a temperature sensor that reduces the flow or switches to a heater module on cold days, so the incoming air does not feel like a draught. Flats without a loft use a wall-mounted unit that draws air from outside through a cored hole.

Loft-mounted PIV

The most common option for houses with a loft. Usually fitted in half a day.

Heated PIV

A heater module tempers the incoming air in cold weather. Useful in homes where people feel draughts.

Wall-mounted PIV for flats

Draws air from outside through an outside wall. Suits flats and homes with no loft space.

Guide prices in County Londonderry

Positive input ventilation (PIV) guide prices in County Londonderry
Work	Guide price
Positive input ventilation (PIV) loft unit, supplied and fitted (per home)	£725–£1,275 inc VAT
Wall-mounted PIV unit for a flat (core drilled through an outside wall) (per flat)	£925–£1,550 inc VAT
Heater module or heated PIV unit (extra over a standard unit) (extra)	£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.

When to get it looked at

Musty smell in wardrobes or behind furniture
The house feels stuffy and damp rather than cold
Washing dried indoors makes everything worse

Rules in Northern Ireland

Northern Ireland has its own building regulations, with ventilation guidance in Technical Booklet K. We design to the Northern Ireland guidance and measure the airflow achieved.

How the job runs

Survey
Fixed quote
Install
Set up
Hand over

Towns we cover in County Londonderry

Questions about positive input ventilation (PIV) 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.

Does PIV really stop condensation?

PIV reduces condensation in most homes because it dilutes moist air and keeps it moving, but it works best alongside working extract fans in the kitchen and bathroom. Leaks, rising damp or a cold bridge need fixing separately.

How much does PIV cost to run?

A standard PIV unit uses very little electricity, comparable to a low-energy light bulb on normal speed. A heated unit costs more in cold spells because the heater switches on when loft air is cold.

Are prices different in County Londonderry?

Our guide prices are adjusted by region. In County Londonderry we use Northern Ireland rates, so positive input ventilation (PIV) loft unit, supplied and fitted is typically £725 to £1,275 inc VAT per home.

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.