Solid wall insulation · Gwynedd
Solid wall insulation in Llangefni
From Llangefni to Bangor (Gwynedd), we price solid wall insulation after a measured survey — no guesswork, and no work starts until the price is agreed in writing. For solid-walled homes in Llangefni, we check wall thickness and age first to confirm there's no cavity to fill.
- Free survey in LL77 and nearby
- Guide price from £75 per m² + scaffold, 0% VAT
- Fixed written price before work starts
Free survey in Llangefni
Postcode, service and a phone number is all we need.
What's included
- In England and Wales, Building Regulations apply when more than half of a wall is treated
- Internal insulation suits single rooms or where the outside can't change
- External insulation keeps room sizes and treats cold bridges well
- Both can be done in stages, elevation by elevation or room by room
Before we quote in Llangefni
Surveys in Llangefni also cover the surrounding LL77 district and towns such as Bangor (Gwynedd) and Caernarfon. Llangefni sits around 8 miles from Bangor (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.
On solid-walled houses in Llangefni, the gable or the most weather-exposed wall is often the place to start.
- Postcode district
- LL77
- County or area
- Gwynedd
- Nation
- Wales
- Nearby
- Bangor (Gwynedd), Caernarfon, Holyhead, Llandudno
Planning and building control in Wales
We check Llangefni 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.
What does solid wall insulation cost?
External systems run at roughly £105–£210 per m² of wall depending on the board and finish. Internal insulation is roughly £75–£130 per m², plus the cost of moving radiators, sockets and kitchen units.
Solid wall insulation prices in Llangefni
| Item | Guide price | Notes |
|---|---|---|
| External (EWI) | £105–£210 per m²0% VAT | By board and finish |
| Internal (IWI) | £75–£130 per m²0% VAT | Plus making good |
| Survey and written recommendation | Free with a quote |
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.
Solid wall insulation in Llangefni: questions
Does solid wall insulation cause condensation?
It can if detailed poorly, particularly internally. A condensation risk check for the proposed build-up and careful detailing at joists, reveals and corners avoid it.
Can I get a grant for solid wall insulation?
Some schemes cover it for eligible households — for example ECO4 until 31 December 2026, Home Energy Scotland's grant and loan, Wales' Warm Homes Nest and NI's Affordable Warmth Scheme. Each has its own eligibility and installer rules; see our grants guide.
Can I do one wall at a time?
Yes. Many owners start with the coldest or most exposed elevation, often a gable end.
Do you cover Llangefni?
Yes — we survey and quote solid wall insulation in Llangefni (LL77) and nearby Bangor (Gwynedd), Caernarfon and Holyhead, with a fixed written price before any work starts.