EPS insulation · Gwynedd
EPS external wall insulation in Caernarfon
From Caernarfon to Llangefni, we price EPS external wall insulation after a measured survey — no guesswork, and no work starts until the price is agreed in writing. Where eaves are shallow on a house in Caernarfon, grey EPS can sometimes avoid the cost of extending the roofline.
- Free survey in LL55 and nearby
- Guide price from £105 per m² + scaffold, 0% VAT
- Fixed written price before work starts
Free survey in Caernarfon
Postcode, service and a phone number is all we need.
What's included
- Light boards mean fewer fixings and a faster install
- Easy to shape around bays, arches and reveals
- Thermal conductivity around 0.031–0.038 W/mK depending on grade
- Finished in silicone, acrylic, mineral render or brick slip
Before we quote in Caernarfon
We cover Caernarfon and nearby Llangefni, Bangor (Gwynedd) and Holyhead. It's roughly 8 miles from Caernarfon to Bangor (Gwynedd), the largest town in Gwynedd. North Wales has many solid stone and slate-built homes, Victorian seaside terraces and post-war council estates.
Parts of Gwynedd 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.
We compare EPS against mineral wool for each Caernarfon enquiry rather than assuming one board suits every wall.
- Postcode district
- LL55
- County or area
- Gwynedd
- Nation
- Wales
- Nearby
- Llangefni, Bangor (Gwynedd), Holyhead, Llandudno
Planning and building control in Wales
For homes in Caernarfon, the local planning authority decides any borderline cases; changing a brick house to render, or work on flats, usually needs an application in Wales.
Welsh Building Regulations expect walls to be upgraded when a substantial area is renewed, and building control signs the work off.
What is EPS insulation?
Expanded polystyrene is a closed-cell foam made from beads that are expanded and moulded into boards. White EPS is the standard grade; grey EPS has graphite added, which reflects radiant heat and improves performance by roughly 15–20%, so a thinner board does the same job. Both are used inside certified render systems where the board, adhesive, fixings, mesh and finish are tested together by the manufacturer.
EPS external wall insulation prices in Caernarfon
| 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
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.
EPS insulation in Caernarfon: 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.
White or grey EPS?
Grey graphite EPS insulates better per millimetre, so it is the pick where space is tight at the eaves or around windows. White EPS is slightly cheaper and works well where the extra thickness isn't a problem.
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.
Do you cover Caernarfon?
Yes — we survey and quote EPS external wall insulation in Caernarfon (LL55) and nearby Llangefni, Bangor (Gwynedd) and Holyhead, with a fixed written price before any work starts.