Dorking, Surrey
Positive input ventilation (PIV) in Dorking
Loft or wall units that gently push filtered air into the home to tackle condensation. Covering Dorking and KT23, RH3 and RH4.
- From £875 inc VAT per home
- Free survey
Condensation in Dorking homes usually has one of two answers: better extract fans, or PIV as well.
Whether the property is in the middle of Dorking 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 Dorking at a glance
- Town
- Dorking, Surrey
- Postcode districts
- KT23, RH3 and RH4
- Nearby
- Great Bookham (4 miles), Leatherhead (4 miles) and Ashtead (6 miles)
- Price region
- South East
- Survey
- Free survey (UK mainland)
What the work involves
PIV works well in houses and flats with general condensation on windows and cold walls. It does not replace extract fans: kitchens and bathrooms still need their own extract to remove steam at source.
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.
Guide prices in Dorking
| Work | Guide price |
|---|---|
| Positive input ventilation (PIV) loft unit, supplied and fitted (per home) | £875–£1,525 inc VAT |
| Wall-mounted PIV unit for a flat (core drilled through an outside wall) (per flat) | £1,100–£1,875 inc VAT |
| Heater module or heated PIV unit (extra over a standard unit) (extra) | £160–£325 inc VAT |
These ranges use our South East rates. Prices include VAT at 20%. You get a fixed written price before any work is booked.
When to get it looked at
- Streaming windows on most mornings in winter
- Black mould on window reveals and in corners of bedrooms
- Musty smell in wardrobes or behind furniture
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 Dorking
What area around Dorking do you work in?
All of Surrey. Near Dorking that includes Great Bookham, Leatherhead, Ashtead and Reigate.
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.
Will PIV make my house cold?
Most units temper or reduce the flow when the incoming air is cold, and a heated unit warms it. Placed correctly on the landing, the air spreads gently rather than blowing on anyone.
Do you cover Dorking and nearby?
Yes. We cover Dorking and nearby places including Great Bookham, Leatherhead, Ashtead and Reigate. Send your postcode and we will confirm.
What is the price of a PIV unit in Dorking?
Guide prices for Dorking use South East rates: positive input ventilation (PIV) loft unit, supplied and fitted is typically £875 to £1,525 inc VAT per home. We confirm a fixed price in writing before any work starts.
Most Dorking PIV jobs are done in half a day, so ask about the next available date.
PIV near Dorking
More services in Dorking
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.