External wall insulation · Cornwall
External wall insulation in Truro
Need external wall insulation in Truro? Tell us about the property and we'll arrange a free survey and a written quote. Whole-house jobs and single elevations are both quoted in Truro; a cold gable or rear wall can be done on its own where it suits.
- Free survey in TR1 and nearby
- Guide price from £105 per m² + scaffold, 0% VAT
- Fixed written price before work starts
Free survey in Truro
Postcode, service and a phone number is all we need.
What the job covers
- Work happens outside, so you can live at home throughout
- Cills, pipes, vents, meter boxes and the roofline detailed as part of the job
- Installing wall insulation in homes is currently zero-rated for VAT until 31 March 2027
- Covers tired brick, pebble dash or failing render with a new finish

Truro: walls, weather and approvals
Surveys in Truro also cover the surrounding TR1 district and towns such as Falmouth and Redruth. Truro is about 8 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.
For homes in Truro, the survey starts with the wall itself: solid brick, stone or concrete, and whether any old render is sound enough to insulate over.
- Postcode district
- TR1
- County or area
- Cornwall
- Nation
- England
- Nearby
- Falmouth, Redruth, Newquay, Camborne
Permissions in England
Planning in Truro follows England's national rules: similar-looking finishes on houses are usually permitted, while flats, commercial premises, conservation areas and streets under an Article 4 direction need an application.
Building control applies once more than half of a wall is insulated or re-rendered, or more than a quarter of the whole building envelope, and your written quote says how that's handled.
How does external wall insulation work?
Heat moves out through a wall faster when the wall is solid or poorly insulated. EWI wraps the outside face in a continuous layer of insulation, so the masonry stays on the warm side and the cold bridges at floor and party-wall junctions are reduced. The boards are bonded with adhesive and, on most walls, mechanically fixed. A base coat with an embedded glass-fibre mesh goes over the top, then a primer and the decorative finish.
Because the wall itself sits inside the insulation, it stays warmer and drier, and the rooms keep their full size. That is the main difference from internal insulation.
External wall insulation prices in Truro
| Item | Guide price | Notes |
|---|---|---|
| EPS system with silicone render | £105–£145 per m²0% VAT | Most common choice for houses |
| Mineral wool system | £125–£170 per m²0% VAT | Non-combustible, vapour-open |
| Brick-slip finish over insulation | £185–£260 per m²0% VAT | Where a brick look is wanted |
| Three-bed semi, EPS + silicone (incl. scaffold) | £10,200–£17,7000% VAT | 80–100 m² of wall; depends on detailing and access |
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
Tell us about the property
Use the quote tool or form, or call. Photos help.
Free survey
We measure, check the walls and confirm approvals.
Fixed written quote
System, details, access, exclusions and VAT in writing.
Installation
Scheduled for suitable weather, with a clear programme.
External wall insulation in Truro: questions
How long does external wall insulation last?
A well-installed render system is commonly expected to last 25–30 years or more, with occasional cleaning and inspection of sealants. The system manufacturer's documentation states the expected service life for the specific build-up.
Does EWI need Building Regulations approval?
In England and Wales, usually. Insulating more than half of a wall's area, or more than a quarter of the building's whole external envelope, counts as renovating a thermal element, so building control needs to be involved and the wall should reach about 0.30 W/m²K where that's practical. Scotland and Northern Ireland have their own building standards processes.
Can EWI go over pebble dash?
Usually yes. The dash is tested for adhesion and hollow areas; sound dash can be insulated over with additional mechanical fixings, while loose areas are removed first.
Do you cover Truro?
Yes — we survey and quote external wall insulation in Truro (TR1) and nearby Falmouth, Redruth and Newquay, with a fixed written price before any work starts.