Mineral wool EWI · Cornwall
Mineral wool external wall insulation in St Austell
Need mineral wool external wall insulation in St Austell? Tell us about the property and we'll arrange a free survey and a written quote. For homes in St Austell near busy roads, mineral wool's sound reduction can be a reason to choose it.
- Free survey in PL25 and nearby
- Guide price from £125 per m² + scaffold, 0% VAT
- Fixed written price before work starts
Free survey in St Austell
Postcode, service and a phone number is all we need.
Part of every quote
- Vapour-open, so moisture in solid walls can dry outwards
- Non-combustible board (typically Euroclass A1 or A2-s1,d0 as part of the system)
- Better sound reduction than foam boards
- Heavier than EPS, so more fixings and careful handling
Before we quote in St Austell
We also cover Bodmin and Truro, close to St Austell. St Austell sits around 21 miles from Redruth. The South West has many stone and solid-walled cottages, exposed coastal properties and a share of post-war system-built houses, including types such as the Cornish Unit.
Parts of Cornwall 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.
Older solid-walled homes in St Austell can suit a vapour-open mineral wool build-up better than foam; the survey checks the wall first.
- Postcode district
- PL25
- County or area
- Cornwall
- Nation
- England
- Nearby
- Bodmin, Truro, Newquay, Falmouth
Planning and building control in England
Before quoting in St Austell, we check whether the property is in a conservation area, under an Article 4 direction or listed, because that decides whether changing the outside needs planning permission.
Insulating or re-rendering more than half of a wall's area brings in Part L of the Building Regulations, so building control is notified and the wall is upgraded to about 0.30 W/m²K where practical.
On residential buildings with a storey 11 metres or more above ground, guidance points to non-combustible external wall materials, and combustible materials are banned in relevant buildings 18 metres and over, so we specify mineral wool systems there.
Why choose mineral wool over EPS?
Two reasons come up most: fire and moisture. Mineral wool doesn't burn, which is why guidance for taller residential buildings points to non-combustible external wall materials. It is also vapour-open, so a solid wall that holds some moisture can keep drying outwards through the insulation and render.
The trade-offs are weight and cost. Slabs are denser, need more fixings and take longer to install, so the price per m² is higher than EPS.
Mineral wool external wall insulation prices in St Austell
| 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 St Austell: questions
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.
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 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.
Do you cover St Austell?
Yes — we survey and quote mineral wool external wall insulation in St Austell (PL25) and nearby Bodmin, Truro and Newquay, with a fixed written price before any work starts.