Positive input ventilation (PIV) in Highgate

Condensation in Highgate homes usually has one of two answers: better extract fans, or PIV as well.

We cover Highgate and the surrounding N6, NW3 and NW5 postcodes as part of our work across Greater London. Surveys for new installations are free on the UK mainland, with a written quote afterwards.

PIV in Highgate at a glance

Town: Highgate, Greater London
Postcode districts: N6, NW3 and NW5
Nearby: Archway (1 mile), Belsize Park (1 mile) and Chalk Farm (2 miles)
Price region: London
Survey: Free survey (UK mainland)

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.

PIV with fan upgrades

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

Loft-mounted PIV

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

Guide prices in Highgate

Positive input ventilation (PIV) guide prices in Highgate
Work	Guide price
Positive input ventilation (PIV) loft unit, supplied and fitted (per home)	£950–£1,675 inc VAT
Wall-mounted PIV unit for a flat (core drilled through an outside wall) (per flat)	£1,200–£2,025 inc VAT
Heater module or heated PIV unit (extra over a standard unit) (extra)	£175–£355 inc VAT

These ranges use our London rates. Prices include VAT at 20%. You get a fixed written price before any work is booked.

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

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.

Questions from Highgate

What is the price of a PIV unit in Highgate?

Guide prices for Highgate use London rates: positive input ventilation (PIV) loft unit, supplied and fitted is typically £950 to £1,675 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 Highgate?

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 Highgate?

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.

Tell us whether your Highgate home has a loft and we can price a PIV unit before visiting.