EPS insulation · South Glamorgan
EPS external wall insulation in Cardiff
If you're planning EPS external wall insulation in Cardiff, start with a free survey: we measure, check the walls and confirm planning and building control for your address. Where eaves are shallow on a house in Cardiff, grey EPS can sometimes avoid the cost of extending the roofline.
- Free survey in CF10 and nearby
- Guide price from £105 per m² + scaffold, 0% 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
- Thermal conductivity around 0.031–0.038 W/mK depending on grade
- Easy to shape around bays, arches and reveals
- Finished in silicone, acrylic, mineral render or brick slip
- Grey graphite EPS reaches a given U-value with a thinner board

Cardiff: walls, weather and approvals
We cover Cardiff and nearby Penarth, Caerphilly and Barry. 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.
EPS is a common choice for two-storey houses, mainly on cost and weight, and we price it alongside mineral wool for homes in Cardiff.
- Postcode district
- CF10
- County or area
- South Glamorgan
- Nation
- Wales
- Nearby
- Penarth, Caerphilly, Barry, Risca
Approvals in Wales
We check Cardiff addresses for conservation areas and listing before quoting, because Welsh permitted development rules don't cover every external change.
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.
When is EPS the right choice?
EPS suits most two-storey houses, bungalows and park homes where the wall is sound and there are no fire-height restrictions. It is a good fit where eaves are shallow, because grey EPS can hit the target with less thickness. On buildings with a storey 11 metres or more above ground, or where the guidance asks for non-combustible materials, mineral wool is used instead.
EPS external wall insulation prices in Cardiff
| Item | Guide price | Notes |
|---|---|---|
| EPS + silicone render | £105–£145 per m²0% VAT | Excluding scaffold |
| Grey EPS uplift | +£4–£8 per m²0% VAT | Thinner board for the same U-value |
| Bungalow, full house | £6,700–£12,8000% VAT | 55–75 m² of wall, including scaffold |
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.
From enquiry to finished wall
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.
EPS insulation in Cardiff: questions
Will woodpeckers damage EPS?
It happens occasionally, especially near woodland. Damage is to the render and board surface and is repaired with a mesh patch and colour-matched finish.
How long does EPS last on a wall?
The board itself doesn't degrade when protected by the render system. Service life depends on the render, sealants and detailing, typically 25–30 years or more with maintenance.
Is EPS insulation safe on a house?
EPS is used inside render systems that are fire-tested as a whole. On low-rise houses it is widely used. On taller buildings, or where guidance calls for non-combustible materials, mineral wool systems are specified instead.
Do you cover Cardiff?
Yes — we survey and quote EPS external wall insulation in Cardiff (CF10) and nearby Penarth, Caerphilly and Barry, with a fixed written price before any work starts.