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External wall insulation · Dyfed

External wall insulation in Carmarthen

From Carmarthen to Llanelli, we price external wall insulation after a measured survey — no guesswork, and no work starts until the price is agreed in writing. Whole-house jobs and single elevations are both quoted in Carmarthen; a cold gable or rear wall can be done on its own where it suits.

  • Free survey in SA31 and nearby
  • Guide price from £105 per m² + scaffold, 0% VAT
  • Fixed written price before work starts

Free survey in Carmarthen

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What the job covers

  • Work happens outside, so you can live at home throughout
  • Boards chosen for the wall: EPS, mineral wool, wood fibre or phenolic
  • Cills, pipes, vents, meter boxes and the roofline detailed as part of the job
  • Installing wall insulation in homes is currently zero-rated for VAT until 31 March 2027
Side gable of a semi-detached house part-way through external wall insulation, with mineral wool slabs, mesh base coat and finished white render

Homes and walls in Carmarthen

We also cover Llanelli and Ammanford, close to Carmarthen. Carmarthen sits around 14 miles from Llanelli. West Wales has a high share of older solid-walled and stone homes, many in exposed coastal or rural settings.

Parts of Dyfed 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 plan EWI in Carmarthen around the details that cause trouble later — cills, eaves, downpipes and the base of the wall above the damp-proof course.

Postcode district
SA31
County or area
Dyfed
Nation
Wales
Nearby
Llanelli, Ammanford, Gorseinon, Swansea

Approvals in Wales

For homes in Carmarthen, the local planning authority decides any borderline cases; changing a brick house to render, or work on flats, usually needs an application in Wales.

Building control in Wales applies to most insulation and re-rendering jobs of this size; the quote states who submits the notice.

What finish can I have?

Most EWI is finished in a thin-coat silicone render in a through-coloured shade, with a 1–2mm grain. Acrylic, mineral (painted), dry-dash and brick-slip finishes are also available. Where planning wants a brick look, brick slips over the insulation keep the street appearance.

External wall insulation prices in Carmarthen

External wall insulation guide prices
ItemGuide priceNotes
EPS system with silicone render£105–£145 per m²0% VATMost common choice for houses
Mineral wool system£125–£170 per m²0% VATNon-combustible, vapour-open
Brick-slip finish over insulation£185–£260 per m²0% VATWhere a brick look is wanted
Three-bed semi, EPS + silicone (incl. scaffold)£10,200–£17,7000% VAT80–100 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

  1. Get a guide price

    Try the online quote tool for a ballpark figure.

  2. Book the survey

    A visit at a time that suits you.

  3. Agree the quote

    Nothing starts until you've signed the written price.

  4. We do the work

    Planned around weather, with you kept informed.

External wall insulation in Carmarthen: 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.

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.

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.

Do you cover Carmarthen?

Yes — we survey and quote external wall insulation in Carmarthen (SA31) and nearby Llanelli, Ammanford and Gorseinon, with a fixed written price before any work starts.

External wall insulation in Carmarthen

Start with a guide price, then fix it with a free survey in Carmarthen.

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