External wall insulation · Hertfordshire
External wall insulation in Welwyn Garden City
We quote external wall insulation for homes in Welwyn Garden City (AL8) and nearby Hatfield and Hertford, with guide prices online and a free survey to fix the price. For homes in Welwyn Garden City, the survey starts with the wall itself: solid brick, stone or concrete, and whether any old render is sound enough to insulate over.
- Free survey in AL8 and nearby
- Guide price from £105 per m² + scaffold, 0% VAT
- Fixed written price before work starts
Free survey in Welwyn Garden City
Postcode, service and a phone number is all we need.
What the job covers
- Installing wall insulation in homes is currently zero-rated for VAT until 31 March 2027
- Covers tired brick, pebble dash or failing render with a new finish
- Boards chosen for the wall: EPS, mineral wool, wood fibre or phenolic
- Work happens outside, so you can live at home throughout
Homes and walls in Welwyn Garden City
We also cover Hatfield and Hertford, close to Welwyn Garden City. Welwyn Garden City is about 13 miles from Watford. The East of England has a mix of post-war estates, inter-war semis and older solid brick and flint cottages, with some system-built council homes on post-war estates.
Much of Hertfordshire 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.
Whole-house jobs and single elevations are both quoted in Welwyn Garden City; a cold gable or rear wall can be done on its own where it suits.
- Postcode district
- AL8
- County or area
- Hertfordshire
- Nation
- England
- Nearby
- Hatfield, Hertford, St Albans, Harpenden
Approvals in England
Planning in Welwyn Garden City follows England's national rules: similar-looking finishes on houses are usually permitted, while flats, commercial premises, conservation areas and streets under an Article 4 direction need an application.
If the work covers more than half of a wall, or a quarter of the building's whole envelope, it counts as renovating a thermal element, with a target of about 0.30 W/m²K where feasible.
What does the survey check before EWI is specified?
- Wall construction and condition, including any damp, cracking or loose render
- Ground levels and the damp-proof course, so the system starts above splash height
- Eaves depth, verges and whether the roofline needs extending
- Window positions, cill depths and reveal space
- Services on the wall: gas, electric meters, flues, soil pipes, satellite dishes and lights
- Planning and Building Regulations position for your property and nation
External wall insulation prices in Welwyn Garden City
| Item | Guide price | Notes |
|---|---|---|
| EPS system with silicone render | £105–£145 per m²0% VAT | Most common choice for houses |
| Mineral wool system | £125–£170 per m²0% VAT | Non-combustible, vapour-open |
| Brick-slip finish over insulation | £185–£260 per m²0% VAT | Where a brick look is wanted |
| Three-bed semi, EPS + silicone (incl. scaffold) | £10,200–£17,7000% VAT | 80–100 m² of wall; depends on detailing and access |
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.
From enquiry to finished wall
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.
External wall insulation in Welwyn Garden City: questions
Can EWI go over pebble dash?
Usually yes. The dash is tested for adhesion and hollow areas; sound dash can be insulated over with additional mechanical fixings, while loose areas are removed first.
How much does external wall insulation cost?
Our guide price for EWI is £105–£170 per m² of wall depending on the system, plus scaffolding. A typical three-bed semi with EPS and silicone render comes to roughly £10,200–£17,700 for the whole house, including scaffold. Installing insulation in a home is zero-rated for VAT until 31 March 2027, so that's the total. You get a fixed written price after a free survey.
How long does external wall insulation last?
A well-installed render system is commonly expected to last 25–30 years or more, with occasional cleaning and inspection of sealants. The system manufacturer's documentation states the expected service life for the specific build-up.
Do you cover Welwyn Garden City?
Yes — we survey and quote external wall insulation in Welwyn Garden City (AL8) and nearby Hatfield, Hertford and St Albans, with a fixed written price before any work starts.