External wall insulation · South Glamorgan
External wall insulation in Barry
Quotes for external wall insulation in Barry list the system, the detailing and the VAT position in writing, so you know exactly what's included. Whole-house jobs and single elevations are both quoted in Barry; a cold gable or rear wall can be done on its own where it suits.
- Free survey in CF63 and nearby
- Guide price from £105 per m² + scaffold, 0% VAT
- Fixed written price before work starts
Free survey in Barry
Postcode, service and a phone number is all we need.
What you get
- Typically takes a 225mm solid brick wall from around 2.1 W/m²K to about 0.30 W/m²K with 90–110mm of board
- Cills, pipes, vents, meter boxes and the roofline detailed as part of the job
- 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

What we look for in Barry
We cover Barry and nearby Penarth, Cardiff and Caerphilly. Barry sits around 7 miles from Cardiff. South Wales has long runs of solid-wall valley terraces, Victorian and Edwardian town housing and post-war council estates.
Exposure to wind-driven rain varies across South Glamorgan: sheltered town streets fare better than walls on high ground or facing the prevailing weather, and the render, beads and cill details are chosen with that in mind.
We plan EWI in Barry around the details that cause trouble later — cills, eaves, downpipes and the base of the wall above the damp-proof course.
- Postcode district
- CF63
- County or area
- South Glamorgan
- Nation
- Wales
- Nearby
- Penarth, Cardiff, Caerphilly, Pontypridd
Planning and building control in Wales
Householder rules in Wales are similar to England's: in Barry, a similar-looking finish on a house is often permitted, but conservation areas, flats and listed buildings need permission or consent.
Welsh Building Regulations expect walls to be upgraded when a substantial area is renewed, and building control signs the work off.
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 Barry
| 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
Enquiry
Send your postcode and a few details.
Measured survey
Walls, damp, eaves, cills and services recorded.
Written price
A fixed price with the specification attached.
Work and handover
Installed, inspected and documents handed over.
External wall insulation in Barry: 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.
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.
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.
Do you cover Barry?
Yes — we survey and quote external wall insulation in Barry (CF63) and nearby Penarth, Cardiff and Caerphilly, with a fixed written price before any work starts.