Allerton, Merseyside
Positive input ventilation (PIV) in Allerton
Loft or wall units that gently push filtered air into the home to tackle condensation. Covering Allerton and L18, L19 and L25.
- From £750 inc VAT per home
- Free survey
PIV is often a good fix for Allerton homes with condensation on every window.
Whether the property is in the middle of Allerton 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 Allerton at a glance
- Town
- Allerton, Merseyside
- Postcode districts
- L18, L19 and L25
- Nearby
- Mossley Hill (1 mile), Woolton (1 mile) and Hunts Cross (1 mile)
- Price region
- North West
- Survey
- Free survey (UK mainland)
PIV for Allerton homes
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.
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 Allerton
| 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 |
Guide prices using North West rates. Prices include VAT at 20%. A guide price is not a quote: we confirm a fixed price in writing first.
Signs it is time to call us
- Washing dried indoors makes everything worse
- You have no loft but still need whole-flat ventilation (wall unit)
- Streaming windows on most mornings in winter
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 Allerton
Do you cover Allerton and nearby?
Yes. We cover Allerton and nearby places including Mossley Hill, Woolton, Hunts Cross and Childwall. Send your postcode and we will confirm.
How much does PIV cost to install?
A loft-mounted PIV unit usually costs £795 to £1,395 including VAT supplied and fitted, and £995 to £1,695 for a wall-mounted unit in a flat. A heater module adds around £145 to £295.
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.
What is the price of a PIV unit in Allerton?
Guide prices for Allerton 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.
Is the survey free in Allerton?
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.
Send a photo of your loft hatch area and landing ceiling for a quicker Allerton quote.
PIV near Allerton
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