Internal wall insulation · Greater London
Internal wall insulation in Harrow
Internal wall insulation in Harrow: free survey, written specification and a fixed price, with the details that keep walls dry planned from the start. For terraced homes in Harrow with attractive brick fronts, one approach is to insulate the front internally and the rear externally.
- Free survey in HA2 and nearby
- Guide price from £75 per m² 0% VAT
- Fixed written price before work starts
Free survey in Harrow
Postcode, service and a phone number is all we need.
What's included
- Keeps the outside of the house exactly as it is
- Needs careful detailing at floor joists, reveals and corners
- Can be done one room at a time during a renovation
- Loses roughly 50–100mm per insulated wall
What we look for in Harrow
Surveys in Harrow also cover the surrounding HA2 district and towns such as Wembley and Northolt. London's housing includes a large stock of Victorian and Edwardian solid-wall terraces, inter-war semis and post-war blocks, and conservation areas cover many streets — so planning is often the first question for external work.
Much of Greater London sits in the lower wind-driven rain exposure bands, which keeps the choice of finishes wide — though hilltop, coastal and exposed gable walls can still need a tougher specification, so we check the actual site.
Where a property in Harrow is in a conservation area or the front elevation must stay unchanged, internal insulation is often the practical route.
- Postcode district
- HA2
- County or area
- Greater London
- Nation
- England
- Nearby
- Wembley, Northolt, Greenford, Ruislip
Permissions in England
Internal insulation rarely needs planning permission, but in England and Wales insulating or replastering more than half of a wall's area involves building control, and listed buildings need consent for internal changes that affect their character.
What are the risks with internal insulation?
Insulating inside makes the masonry colder, so moisture risk rises. Weak points are where floor joists bear into the wall, window reveals and corners. A condensation risk check for the build-up, a continuous vapour control layer where specified, and returning insulation into reveals deal with most of it.
Internal wall insulation prices in Harrow
| Item | Guide price | Notes |
|---|---|---|
| Insulated plasterboard, supplied and skimmed | £75–£110 per m²0% VAT | |
| Insulated stud wall | £90–£130 per m²0% VAT | |
| Typical bedroom, one external wall | £1,795–£2,9950% VAT | Including making good |
Confirmed by a fixed written quote after survey. 0% VAT: installing insulation in a home is zero-rated until 31 March 2027, so these figures are the total; 5% applies from 1 April 2027.
How it works
Tell us about the property
Use the quote tool or form, or call. Photos help.
Free survey
We measure, check the walls and confirm approvals.
Fixed written quote
System, details, access, exclusions and VAT in writing.
Installation
Scheduled for suitable weather, with a clear programme.
Internal wall insulation in Harrow: questions
How much room space will I lose?
Usually 50–100mm on each insulated wall, depending on the system.
Is internal insulation cheaper than external?
Per m² usually yes, but the cost of moving fittings and redecorating narrows the gap on whole-house jobs.
Can I stay in the house?
Yes, but each room is out of use while it's worked on, typically 3–5 days.
Do you cover Harrow?
Yes — we survey and quote internal wall insulation in Harrow (HA2) and nearby Wembley, Northolt and Greenford, with a fixed written price before any work starts.