Passivhaus and EnerPHit · Northamptonshire
Passivhaus and EnerPHit windows in Northampton
Looking at Passivhaus and EnerPHit windows for a home in Northampton? We survey, quote and fit across Northamptonshire, and the NN1 postcode district is part of that.

The windows and installation detail low-energy builds depend on. Passivhaus is a building standard from the Passive House Institute; EnerPHit is its version for retrofits.
Winter light and glass choice in Northampton
On the shortest day, Northampton gets about 7 h 42 min of daylight and the midday sun reaches only about 14° above the horizon. Low winter sun means north-facing rooms here gain little solar heat, which is where triple glazing’s lower heat loss helps most.
Guide prices in Northampton
| Guide | Supply and fit, inc VAT |
|---|---|
| uPVC low-energy window medium, deep frame, Uw about 0.8 or better | £1,395 – £1,795 |
| Timber low-energy window medium, thermally broken | £2,395 – £2,995 |
| Alu-clad timber low-energy window medium, certified-component systems on request | £2,695 – £3,395 |
Guide prices. Your written quote after the free survey fixes the price for the specification shown.
Rules for Passivhaus and EnerPHit in England
In England, replacement windows must meet 1.4 W/m²K, or a Window Energy Rating of band B or better. Replacement windows are a controlled fitting. A competent person scheme installer (such as FENSA or Certass) self-certifies the work and notifies the council within 30 days; otherwise a building control body approves it.
Before ordering: Replacing windows on a house is normally permitted development if the new ones look similar. New upper-floor windows in a side wall must be obscure glazed and fixed, or open only above 1.7 m. Flats and maisonettes have no householder permitted development rights, so a change that alters their appearance needs planning permission. An Article 4 direction in a conservation area may mean permission is needed, and listed buildings need listed building consent.
How it works
The surveyor measures every opening, checks ventilation, escape windows and safety-glass zones, and talks through styles. Your written quote lists each item with its glass build-up and U-value, and the price is fixed for that specification.
- Guide prices published, not hidden
- No pressure: the quote is yours to keep
- Frames, glass and fitting in one contract
- Advice on planning and consents before you order
Questions from Northampton
What is EnerPHit?
The Passive House Institute’s standard for retrofitting existing buildings, with slightly relaxed targets compared with new Passivhaus builds.
Is triple glazing enough for Passivhaus?
Triple glass is the starting point. The frame, spacers and installation all have to perform too.
How long does it take to get Passivhaus and EnerPHit windows fitted in Northampton?
After the survey, typical manufacture time is 8 to 14 weeks, and most homes are fitted in 1 to 4 days.
Do I need permission for Passivhaus and EnerPHit windows in Northampton?
In England, like-for-like replacements on a house are normally permitted development; flats need permission if the change alters their appearance, Article 4 areas may need permission, and listed buildings need listed building consent. Check whether your street is in a conservation area or covered by an Article 4 direction before changing the style.
Nearby
We also cover nearby Wellingborough (14 km), Daventry (19 km), Rushden (20 km) and Kettering (20 km).
Other products in Northampton
- uPVC windows
- Aluminium windows
- Timber windows
- Alu-clad timber windows
- Casement windows
- Flush casement windows
- Tilt and turn windows
- Sash windows
- Bay and bow windows
- Fixed and picture windows
- Composite front doors
- French doors
- Sliding patio doors
- Bifold doors
- Glass-only replacement
- Acoustic triple glazing
- Security glazing
- Whole-house replacement
- New builds and self-builds
- Period homes and conservation areas
- Flats and apartments
Passivhaus and EnerPHit in Northampton: book your free survey
Written quote fixed for the specification, after a free survey. Building Regulations sign-off by a competent person scheme installer or building control, as the law requires in England.
