Commercial EWI · South Glamorgan
Commercial and public building EWI in Cardiff
If you're planning commercial external wall insulation in Cardiff, start with a free survey: we measure, check the walls and confirm planning and building control for your address. Schools and community buildings around Cardiff are usually phased by elevation, with noisy stages in holidays where possible.
- Free survey in CF10 and nearby
- Guide price from £110 per m² + scaffold, + VAT
- Fixed written price before work starts
Free survey in Cardiff
Postcode, service and a phone number is all we need.
Part of every quote
- Contract roles under CDM 2015 agreed at the start
- Planning applications supported with drawings and finish samples
- Clear handover file with system documentation
- Colour and texture options to suit brand or setting

Cardiff: walls, weather and approvals
Surveys in Cardiff also cover the surrounding CF10 district and towns such as Penarth and Caerphilly. 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.
For commercial premises in Cardiff, we programme the work around opening hours so the building can keep trading.
- Postcode district
- CF10
- County or area
- South Glamorgan
- Nation
- Wales
- Nearby
- Penarth, Caerphilly, Barry, Risca
Permissions in Wales
For homes in Cardiff, the local planning authority decides any borderline cases; changing a brick house to render, or work on flats, usually needs an application in Wales.
In Wales, insulating or re-rendering more than half of a wall's area is treated as renovating a thermal element under Approved Document L (Wales), so building control is involved before work starts.
Wales applies its own external wall fire rules, updated in 2025; on taller residential buildings we specify non-combustible mineral wool systems.
Does commercial EWI need planning permission?
Generally yes — permitted development rights for external wall changes are written for houses. Applications need elevations showing the projection, finish and colours, and details at eaves and openings.
Commercial and public building EWI prices in Cardiff
| Item | Guide price | Notes |
|---|---|---|
| Insulated render system | £110–£200 per m²+ VAT | Priced on survey |
| Render refurbishment without insulation | £55–£95 per m²+ VAT | Silicone or mineral |
| Access and scaffold | Per building | Includes edge protection |
Confirmed by a fixed written quote after survey. Business prices shown before VAT, which is added at 20%. Buildings used solely for a relevant charitable purpose can qualify for 0% on insulation.
What happens next
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.
Commercial EWI in Cardiff: questions
Is VAT 0% on commercial insulation?
Usually not. The zero rate covers insulation installed in residential accommodation and, since 1 February 2024, buildings used solely for a relevant charitable purpose, such as many charity-run village halls. Other commercial work is standard-rated.
Do you handle the planning application?
We provide the technical information, drawings and samples an application needs; your agent or our designer can submit it.
Do you provide a maintenance plan?
Yes — the handover includes the system documents and recommended inspection and cleaning intervals.
Do you cover Cardiff?
Yes — we survey and quote commercial external wall insulation in Cardiff (CF10) and nearby Penarth, Caerphilly and Barry, with a fixed written price before any work starts.