Positive input ventilation (PIV) in Wavertree

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

Whether the property is in the middle of Wavertree or one of the villages around it, the process is the same: a look at the building, a written price, then fitting and testing on the agreed day.

PIV in Wavertree at a glance

Town: Wavertree, Merseyside
Postcode districts: L15, L16 and L18
Nearby: Childwall (1 mile), Old Swan (1 mile) and Mossley Hill (2 miles)
Price region: North West
Survey: Free survey (UK mainland)

What the work involves

It does not replace extract fans: kitchens and bathrooms still need their own extract to remove steam at source. On survey we check the loft, the landing position and the existing fans, and we tell you if PIV is not the right answer.

Wall-mounted PIV for flats

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

PIV with fan upgrades

PIV plus humidity-controlled extract fans in the kitchen and bathroom for the most stubborn condensation.

Guide prices in Wavertree

Positive input ventilation (PIV) guide prices in Wavertree
Work	Guide price
Positive input ventilation (PIV) loft unit, supplied and fitted (per home)	£750–£1,325 inc VAT
Wall-mounted PIV unit for a flat (core drilled through an outside wall) (per flat)	£950–£1,600 inc VAT
Heater module or heated PIV unit (extra over a standard unit) (extra)	£140–£280 inc VAT

North West rates shown. Prices include VAT at 20%. The fixed price is confirmed in writing after we have seen the job.

When to get it looked at

You have no loft but still need whole-flat ventilation (wall unit)
Streaming windows on most mornings in winter
Black mould on window reveals and in corners of bedrooms

Rules that apply in England

English building work follows Approved Document F (2021 edition) for ventilation rates, installation and commissioning. 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.

Questions from Wavertree

What is the price of a PIV unit in Wavertree?

Guide prices for Wavertree use North West rates: positive input ventilation (PIV) loft unit, supplied and fitted is typically £750 to £1,325 inc VAT per home. We confirm a fixed price in writing before any work starts.

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.

Is the survey free in Wavertree?

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.

How do I get a price for a PIV unit in Wavertree?

Use the guide price tool, the form on this page, live chat, WhatsApp or call 0800 088 6341. A postcode and a couple of photos help us give you a useful answer first time.

Get a PIV guide price for your Wavertree home online, then confirm it on a free survey.