Mineral wool EWI · Wales
Mineral wool external wall insulation in Gwent
Homes and buildings across Gwent — from Newport (Gwent) to Pontypool — can get a free survey and written quote for mineral wool external wall insulation. Older solid-walled homes in Gwent can suit a vapour-open mineral wool build-up better than foam; the survey checks the wall first.
- Free survey and fixed written price
- Guide price from £125 per m² + scaffold, 0% VAT
- Planning and building control checked for Wales
Free survey in Gwent
Tell us the postcode and what you need.
What's included
- Heavier than EPS, so more fixings and careful handling
- Used on blocks of flats and buildings with storeys above 11m
- Non-combustible board (typically Euroclass A1 or A2-s1,d0 as part of the system)
- Better sound reduction than foam boards
- Vapour-open, so moisture in solid walls can dry outwards

Before we quote 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.
Older solid-walled homes in Gwent can suit a vapour-open mineral wool build-up better than foam; the survey checks the wall first.
- Nation
- Wales
- Region
- South Wales
- Towns covered
- Newport (Gwent), Cwmbran, Pontypool, Ebbw Vale, Caerphilly, Risca, Abergavenny, Monmouth
- Guide price
- From £125 per m² + scaffold · 0% VAT
Wales: planning and regulations
Permitted development rules for houses in Wales are similar to England's: a similar-appearance finish on a house is often permitted, while conservation areas, National Parks, Areas of Outstanding Natural Beauty, flats, commercial buildings and listed buildings need permission or consent. Your local planning authority has the final word.
The Building Regulations as they apply in Wales treat insulating or re-rendering more than half of a wall's area, or more than a quarter of the building's whole envelope, as renovating a thermal element, with Approved Document L (Wales) setting the target. Building control is involved before work starts.
Wales applies its own amended fire rules for external walls, including the combustible materials ban for relevant buildings and guidance for residential buildings between 11 and 18 metres, updated by the Building (Amendment) (Wales) Regulations 2025.
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 Gwent
| 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 Gwent: questions
Is mineral wool needed for a bungalow?
Rarely for fire reasons. It may still be chosen on a damp-prone solid wall where a vapour-open build-up is wanted.
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.
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.
Do you cover all of Gwent?
Yes. We survey and quote mineral wool external wall insulation across Gwent, including Newport (Gwent), Cwmbran, Pontypool, Ebbw Vale, Caerphilly.
Do I need planning permission in Wales?
Permitted development rules for houses in Wales are similar to England's: a similar-appearance finish on a house is often permitted, while conservation areas, National Parks, Areas of Outstanding Natural Beauty, flats, commercial buildings and listed buildings need permission or consent. We check your address before quoting.