External wall insulation · Berkshire
External wall insulation in Windsor
Looking for external wall insulation in Windsor? We survey homes across Windsor and the SL4 area, then give you a fixed written price before any work starts. Whole-house jobs and single elevations are both quoted in Windsor; a cold gable or rear wall can be done on its own where it suits.
- Free survey in SL4 and nearby
- Guide price from £105 per m² + scaffold, 0% VAT
- Fixed written price before work starts
Free survey in Windsor
Postcode, service and a phone number is all we need.
What you get
- Installing wall insulation in homes is currently zero-rated for VAT until 31 March 2027
- Typically takes a 225mm solid brick wall from around 2.1 W/m²K to about 0.30 W/m²K with 90–110mm of board
- Boards chosen for the wall: EPS, mineral wool, wood fibre or phenolic
- Work happens outside, so you can live at home throughout

Before we quote in Windsor
As well as Windsor itself, we quote in Slough, Egham and Staines. Windsor is about 16 miles from Reading. Homes across the South East range from inter-war semis and post-war estates, which are mostly cavity-walled, to older solid-walled cottages and Victorian town terraces.
Much of Berkshire 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.
We plan EWI in Windsor around the details that cause trouble later — cills, eaves, downpipes and the base of the wall above the damp-proof course.
- Postcode district
- SL4
- County or area
- Berkshire
- Nation
- England
- Nearby
- Slough, Egham, Staines, Maidenhead
England: planning and regulations
Planning in Windsor 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.
Insulating or re-rendering more than half of a wall's area brings in Part L of the Building Regulations, so building control is notified and the wall is upgraded to about 0.30 W/m²K where practical.
What finish can I have?
Most EWI is finished in a thin-coat silicone render in a through-coloured shade, with a 1–2mm grain. Acrylic, mineral (painted), dry-dash and brick-slip finishes are also available. Where planning wants a brick look, brick slips over the insulation keep the street appearance.
External wall insulation prices in Windsor
| 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.
How it works
Get a guide price
Try the online quote tool for a ballpark figure.
Book the survey
A visit at a time that suits you.
Agree the quote
Nothing starts until you've signed the written price.
We do the work
Planned around weather, with you kept informed.
External wall insulation in Windsor: 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 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.
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.
Do you cover Windsor?
Yes — we survey and quote external wall insulation in Windsor (SL4) and nearby Slough, Egham and Staines, with a fixed written price before any work starts.