Carshalton, Greater London
Positive input ventilation (PIV) in Carshalton
Loft or wall units that gently push filtered air into the home to tackle condensation. Covering Carshalton and SM1, SM5 and SM6.
- From £950 inc VAT per home
- Free survey
PIV can suit Carshalton houses and flats because it treats the whole home from one quiet unit.
Whether the property is in the middle of Carshalton 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 Carshalton at a glance
- Town
- Carshalton, Greater London
- Postcode districts
- SM1, SM5 and SM6
- Nearby
- Wallington (1 mile), St Helier (1 mile) and Sutton (2 miles)
- Price region
- London
- Survey
- Free survey (UK mainland)
How we approach PIV in Carshalton
Flats without a loft use a wall-mounted unit that draws air from outside through a cored hole. PIV works well in houses and flats with general condensation on windows and cold walls.
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 Carshalton
| 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 |
London rates shown. Prices include VAT at 20%. The fixed price is confirmed in writing after we have seen the job.
Common reasons people call
- 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 Carshalton
Do you cover Carshalton and nearby?
Yes. We cover Carshalton and nearby places including Wallington, St Helier, Sutton and Belmont. Send your postcode and we will confirm.
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.
What is the price of a PIV unit in Carshalton?
Guide prices for Carshalton 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.
Is the survey free in Carshalton?
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.
Get a PIV guide price for your Carshalton home online, then confirm it on a free survey.
PIV near Carshalton
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