HOUSESRENDERINGRender · Protect · Enhance

South West

External Wall Insulation in Cornwall

EWI systems that insulate solid walls externally and finish them in a warranted render topcoat.

Our external wall insulation work in Cornwall starts with a free survey, because guessing at a render specification is how jobs go wrong.

The prevailing picture in Cornwall is granite and cob cottages, slate-hung walls and exposed coastal housing. That means driving-rain penetration and salt damage on exposed elevations comes up more here than almost anywhere else. Local conditions bring severe driving rain and salt-laden coastal exposure, and that has a direct bearing on which systems are worth specifying.

Local factor. Exposure here is category-defining — dashed and roughcast finishes genuinely outperform smooth render on west-facing coastal walls.

Is external wall insulation right for a Cornwall property?

Choose EWI on solid-wall, no-fines or non-traditional construction where you want a genuine thermal upgrade rather than just a new finish.

That decision gets made at the survey, not on the phone. We will tell you plainly if a different system would serve the building better — including when a cheaper one would.

Guide price and specification

Guide price£135–£210 per m²
Applied thickness50-150mm insulation plus render system
Curing / dryingStaged, 7-10 days total
Guarantee25 years
CoverageAll of Cornwall — 10 towns and cities

Indicative only, excluding scaffold, stripping and repairs. Try the guide-price tool for a range based on your property.

What is included

  • EPS, mineral wool and phenolic boards
  • 50mm to 150mm thicknesses
  • Mechanical and adhesive fixing
  • Reinforced basecoat with mesh
  • Silicone or acrylic topcoat
  • Window and door reveal detailing
  • Eaves and verge extensions
  • Fire-rated mineral wool options

External Wall Insulation across Cornwall

External Wall Insulation in Cornwall

Tell us about the property and we will call you back to arrange a survey.

Free survey · no obligation · fixed written quote

Guaranteed workmanship
Free written survey
System-warranted builds
UK-wide coverage
Fixed price, no surprises

What happens next

Four steps from enquiry to finished wall

Free survey

We visit, test the substrate, measure up and identify what caused any existing failure.

Written quote

An itemised fixed price with the system named, materials specified and scaffold included.

Booked in

An agreed start date, scaffold arranged, and a clear run of days set aside for your job.

Finished and guaranteed

Site cleared, scaffold struck, guarantee documents and system warranty issued.

FAQs

External Wall Insulation in Cornwall — questions

Will you need scaffolding?

For anything above single storey, yes — it is safer and produces a better finish than working off ladders or towers. Scaffold is included and itemised in the quote.

How long before I can paint new render?

Through-coloured systems need no painting at all. Sand and cement should cure for around 28 days before masonry paint goes anywhere near it.

Do you take a deposit?

For most domestic jobs we take a deposit to cover materials and scaffold, with the balance on completion. Terms are set out clearly in the written quote.

Can you match my existing render?

Usually, yes. We colour and texture match as closely as we can, though weathered render never matches a fresh batch exactly — we will be honest about how visible a patch will be.

Will EWI make my house look different?

The walls become 70-200mm thicker, so reveals get deeper and the eaves usually need extending. Done properly it looks intentional; done cheaply it looks like a box.

Can EWI cause damp?

Correctly specified it reduces damp risk by keeping the wall warm. Problems come from poor detailing at reveals, sills and penetrations, or from using a non-breathable system on a wall that needed one.

External Wall Insulation quotes across Cornwall

Free survey, honest advice on whether this is the right system, and a fixed written price.

Call Get a quote