External wall insulation · Wales
External wall insulation in West Glamorgan
External wall insulation across West Glamorgan: measured survey, clear specification and a fixed written price before any work starts. For homes in West Glamorgan, 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 and fixed written price
- Guide price from £105 per m² + scaffold, 0% VAT
- Planning and building control checked for Wales
Free survey in West Glamorgan
Tell us the postcode and what you need.
What you get
- Cills, pipes, vents, meter boxes and the roofline detailed as part of the job
- Work happens outside, so you can live at home throughout
- Boards chosen for the wall: EPS, mineral wool, wood fibre or phenolic
- Covers tired brick, pebble dash or failing render with a new finish
- Installing wall insulation in homes is currently zero-rated for VAT until 31 March 2027

Local considerations in West Glamorgan
South Wales has long runs of solid-wall valley terraces, Victorian and Edwardian town housing and post-war council estates.
Parts of West Glamorgan fall in the higher wind-driven rain exposure bands, especially coastal and upland sites, so render specification, movement joints and detailing at cills, verges and the base of the wall matter more than usual.
For homes in West Glamorgan, the survey starts with the wall itself: solid brick, stone or concrete, and whether any old render is sound enough to insulate over.
- Nation
- Wales
- Region
- South Wales
- Towns covered
- Swansea, Neath, Briton Ferry, Port Talbot, Gorseinon
- Guide price
- From £105 per m² + scaffold · 0% VAT
Planning and building control in Wales
Permitted development rules for houses in Wales are similar to England's: a similar-appearance finish on a house is often permitted, while conservation areas, National Parks, Areas of Outstanding Natural Beauty, flats, commercial buildings and listed buildings need permission or consent. Your local planning authority has the final word.
The Building Regulations as they apply in Wales treat insulating or re-rendering more than half of a wall's area, or more than a quarter of the building's whole envelope, as renovating a thermal element, with Approved Document L (Wales) setting the target. Building control is involved before work starts.
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 West Glamorgan
| 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.
What happens next
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 West Glamorgan: questions
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.
Does external wall insulation cause damp?
Not when it is specified and detailed properly. Problems usually come from poor detailing: no starter track above the damp-proof course, gaps at cills and penetrations, or a vapour-closed system on a wall that needs to breathe. The survey checks moisture, ground levels and the wall type before a system is chosen.
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.
Do you cover all of West Glamorgan?
Yes. We survey and quote external wall insulation across West Glamorgan, including Swansea, Neath, Briton Ferry, Port Talbot, Gorseinon.
Do I need planning permission in Wales?
Permitted development rules for houses in Wales are similar to England's: a similar-appearance finish on a house is often permitted, while conservation areas, National Parks, Areas of Outstanding Natural Beauty, flats, commercial buildings and listed buildings need permission or consent. We check your address before quoting.