Wales
External Wall Insulation in South Glamorgan
EWI systems that insulate solid walls externally and finish them in a warranted render topcoat.
Our external wall insulation work in South Glamorgan starts with a free survey, because guessing at a render specification is how jobs go wrong.
South Glamorgan is characterised by Victorian and Edwardian terraces, Cardiff suburban housing and coastal properties, with solid-wall terrace damp and coastal weathering at Barry and Penarth the recurring theme on the properties we survey. South Glamorgan sits in a part of the UK that gets wet with coastal exposure along the Severn estuary — worth factoring into any render decision.
Local factor. Cardiff's victorian terraces are largely solid-wall, and external insulation with a breathable render is the upgrade that suits them best.
Is external wall insulation right for a South Glamorgan 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 thickness | 50-150mm insulation plus render system |
| Curing / drying | Staged, 7-10 days total |
| Guarantee | 25 years |
| Coverage | All of South Glamorgan — 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 South Glamorgan
External Wall Insulation in South Glamorgan
Tell us about the property and we will call you back to arrange a survey.
Other services in South Glamorgan
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 South Glamorgan — questions
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.
How long does a rendering job take?
A typical three-bedroom semi is usually one to two weeks on site including scaffold, preparation, application and finishing. Weather, wall condition and the system chosen all move that.
Do I need planning permission to render my house?
Usually not on a standard house, but you will if the property is listed, in a conservation area, or if rendering would significantly change its appearance. We flag it at survey.
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.
External Wall Insulation quotes across South Glamorgan
Free survey, honest advice on whether this is the right system, and a fixed written price.