External wall insulation in Welwyn Garden City
Every external wall insulation job in Welwyn Garden City starts with a free survey of your walls: what they are built from, how they have weathered, and what the details around windows, eaves and services will need.
Homes in and around Welwyn Garden City
Welwyn Garden City is in the AL8 postcode district, about 13 miles from Watford. 6 other towns we cover are within 25 miles.
Our Welwyn Garden City surveys cover the AL8 district and the surrounding area, including Hatfield, Hertford and St Albans.
Most EWI failures start at the edges rather than the middle of a wall, so the quote for your Welwyn Garden City home sets out how each detail will be built.
Nearby towns we cover: Hatfield (3 miles), Hertford (6 miles), St Albans (6 miles), Harpenden (7 miles), Stevenage (7 miles), Potters Bar (8 miles).
External wall insulation prices in Welwyn Garden City
Guide prices for external wall insulation in Welwyn Garden City run from about £109 to £175 per square metre installed, depending on system and finish; scaffolding priced per house, with VAT at 0% on homes until 31 March 2027.
Bays, gables, conservatory junctions and narrow side passages take longer than plain walls, so the survey prices your actual house rather than an average.
Popular services in Welwyn Garden City
- EWI installation
- Insulating lime render
- Mineral & silicate render
- Solid wall insulation
- Bungalow EWI
- Terraced house EWI
- Semi-detached EWI
- Park home insulation
- Flats & low-rise blocks
- EWI repairs
- All 24 services
Rules that apply in Welwyn Garden City
- Building regulations
- Insulating more than half of a wall, or more than a quarter of the whole building envelope, counts as renovating a thermal element under the Building Regulations, so the wall should reach 0.30 W/m²K where that is technically, functionally and economically feasible, and building control must be involved.
- VAT
- Installing insulation in a home is zero-rated for VAT until 31 March 2027, then 5%.
Checked October 2026. Rules change, so we confirm them for your address at survey.
External wall insulation in Welwyn Garden City: questions
How much should I budget for external wall insulation in Welwyn Garden City?
Budget around £109–£175 per square metre of wall for the system and finish, plus scaffolding priced per house. The survey measures your walls in Welwyn Garden City and fixes the total in writing.
Do you cover Hatfield as well as Welwyn Garden City?
Yes. From Welwyn Garden City we also cover Hatfield, Hertford and St Albans, and the rest of Hertfordshire.
How long will the work take in Welwyn Garden City?
Two to six weeks on site for most houses, depending on size: bungalows are quicker, detached houses longer, weather allowing. Render isn't applied in rain or frost.