Solid wall insulation · Gwent
Solid wall insulation in Monmouth
If you're planning solid wall insulation in Monmouth, start with a free survey: we measure, check the walls and confirm planning and building control for your address. For Monmouth homeowners weighing external against internal insulation, the survey sets out both with prices.
- Free survey in NP25 and nearby
- Guide price from £75 per m² + scaffold, 0% VAT
- Fixed written price before work starts
Free survey in Monmouth
Postcode, service and a phone number is all we need.
Part of every quote
- Solid walls can lose heat roughly twice as fast as an insulated cavity wall
- Breathable options for stone and lime-mortared walls
- Internal insulation suits single rooms or where the outside can't change
- In England and Wales, Building Regulations apply when more than half of a wall is treated
Homes and walls in Monmouth
Surveys in Monmouth also cover the surrounding NP25 district and towns such as Abergavenny and Pontypool. It's roughly 20 miles from Monmouth to Newport (Gwent), the largest town in Gwent. 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 Gwent: 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 solid-walled homes in Monmouth, we check wall thickness and age first to confirm there's no cavity to fill.
- Postcode district
- NP25
- County or area
- Gwent
- Nation
- Wales
- Nearby
- Abergavenny, Pontypool, Cwmbran, Newport (Gwent)
Planning and building control in Wales
We check Monmouth 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.
How can I tell if my walls are solid?
Measure the wall thickness at a window or door: about 225mm (9 inches) of brick usually means solid, while 260mm or more often means a cavity. On exposed brick, a pattern with bricks laid end-on (headers) every few courses points to solid construction. Stone walls are usually solid regardless of thickness. Age is a strong clue too — most homes built before the 1920s are solid-walled.
Solid wall insulation prices in Monmouth
| 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.
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.
Solid wall insulation in Monmouth: 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 Monmouth?
Yes — we survey and quote solid wall insulation in Monmouth (NP25) and nearby Abergavenny, Pontypool and Cwmbran, with a fixed written price before any work starts.