External wall insulation · Wales
External wall insulation in Mid Glamorgan
Homes and buildings across Mid Glamorgan — from Rhondda to Merthyr Tydfil — can get a free survey and written quote for external wall insulation. For homes in Mid 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 Mid Glamorgan
Tell us the postcode and what you need.
Part of every quote
- Work happens outside, so you can live at home throughout
- Installing wall insulation in homes is currently zero-rated for VAT until 31 March 2027
- Cills, pipes, vents, meter boxes and the roofline detailed as part of the job
- Typically takes a 225mm solid brick wall from around 2.1 W/m²K to about 0.30 W/m²K with 90–110mm of board
- Covers tired brick, pebble dash or failing render with a new finish
Mid Glamorgan: walls, weather and approvals
South Wales has long runs of solid-wall valley terraces, Victorian and Edwardian town housing and post-war council estates.
Parts of Mid 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 Mid 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
- Rhondda, Bridgend, Merthyr Tydfil, Aberdare, Pontypridd, Maesteg
- Guide price
- From £105 per m² + scaffold · 0% VAT
Permissions 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.
Which homes is EWI suited to?
EWI is mainly used on solid-walled houses (most homes built before about 1920), on post-war concrete and steel-framed houses, on homes where cavity fill isn't possible, and on bungalows and park homes. It also suits flats and blocks where the whole building is treated at once.
It is less straightforward where the walls face a pavement with no room to project, on listed buildings, or where planning rules want the existing brick or stone left visible. A survey picks these up before you commit.
External wall insulation prices in Mid 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 Mid Glamorgan: questions
Does EWI need Building Regulations approval?
In England and Wales, usually. Insulating more than half of a wall's area, or more than a quarter of the building's whole external envelope, counts as renovating a thermal element, so building control needs to be involved and the wall should reach about 0.30 W/m²K where that's practical. Scotland and Northern Ireland have their own building standards processes.
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.
Do you cover all of Mid Glamorgan?
Yes. We survey and quote external wall insulation across Mid Glamorgan, including Rhondda, Bridgend, Merthyr Tydfil, Aberdare, Pontypridd.
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.