Mineral wool EWI · Gwent
Mineral wool external wall insulation in Monmouth
Mineral wool external wall insulation in Monmouth: free survey, written specification and a fixed price, with the details that keep walls dry planned from the start. Older solid-walled homes in Monmouth can suit a vapour-open mineral wool build-up better than foam; the survey checks the wall first.
- Free survey in NP25 and nearby
- Guide price from £125 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
- Used on blocks of flats and buildings with storeys above 11m
- Finished in mineral or silicone render, or brick slip
- Vapour-open, so moisture in solid walls can dry outwards
- Heavier than EPS, so more fixings and careful handling
Local considerations in Monmouth
We cover Monmouth and nearby Abergavenny, Pontypool and Cwmbran. Monmouth sits around 20 miles from Newport (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 homes in Monmouth near busy roads, mineral wool's sound reduction can be a reason to choose it.
- Postcode district
- NP25
- County or area
- Gwent
- Nation
- Wales
- Nearby
- Abergavenny, Pontypool, Cwmbran, Newport (Gwent)
Approvals in Wales
Householder rules in Wales are similar to England's: in Monmouth, a similar-looking finish on a house is often permitted, but conservation areas, flats and listed buildings need permission or consent.
Welsh Building Regulations expect walls to be upgraded when a substantial area is renewed, and building control signs the work off.
Wales applies its own external wall fire rules, updated in 2025; on taller residential buildings we specify non-combustible mineral wool systems.
What about noise?
Dense mineral wool adds mass and absorbs sound, so homes beside main roads or railways often notice a quieter interior, particularly where windows are also upgraded. The improvement depends on the whole wall and windows, so we don't quote decibel figures without testing.
Mineral wool external wall insulation prices in Monmouth
| Item | Guide price | Notes |
|---|---|---|
| Mineral wool + mineral or silicone render | £125–£170 per m²0% VAT | Excluding scaffold |
| Mineral wool + brick slip | £195–£260 per m²0% VAT | Heavier slip systems need extra fixings |
| Three-bed semi, full house | £11,800–£20,2000% VAT | 80–100 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
Get a guide price
Try the online quote tool for a ballpark figure.
Book the survey
A visit at a time that suits you.
Agree the quote
Nothing starts until you've signed the written price.
We do the work
Planned around weather, with you kept informed.
Mineral wool EWI in Monmouth: questions
Does mineral wool get wet?
It is water-repellent and protected by the render system. Like any insulation it must not be left exposed to rain during installation, so boards are covered and work stops in wet weather.
Is mineral wool better than EPS?
Not always better — different. Mineral wool wins on fire performance, breathability and acoustics; EPS wins on cost, weight and thinner boards for the same U-value. The wall, the building height and your priorities decide it.
Can mineral wool EWI have a brick finish?
Yes. Brick slips can be bonded over mineral wool systems designed for them, with additional fixings for the extra weight.
Do you cover Monmouth?
Yes — we survey and quote mineral wool external wall insulation in Monmouth (NP25) and nearby Abergavenny, Pontypool and Cwmbran, with a fixed written price before any work starts.