Updated 26 October 2026 · SK Home Improvements
External render is a coating applied to outside walls to protect them from the weather and give a smooth or textured finish. The main types are sand and cement, monocouche, silicone, acrylic and lime. Rendering a house typically costs £7,000–£16,000 including VAT, depending on wall area, access, preparation and the render system chosen.
What is external render?
External render is a coating of mortar or a modern polymer-based material applied to the outside walls of a building to protect them from rain and give a finished appearance. It can refresh an older house, cover mismatched brickwork after an extension, or form the finish on external wall insulation. Render is usually applied in layers over a prepared wall, with metal or plastic beads forming neat edges and corners.
What types of render are there?
The main types of render used on UK homes are sand and cement, monocouche, silicone, acrylic and lime. They differ in finish, flexibility, breathability and upkeep.
| Render | Finish | Main points |
|---|---|---|
| Sand and cement | Smooth or textured; usually painted | Traditional and lower cost; can crack and needs repainting |
| Monocouche | Through-coloured, often scraped | Cement-based, applied in one thick coat; no painting needed |
| Silicone | Thin, through-coloured, fine texture | Water-repellent and breathable; helps the wall stay clean |
| Acrylic | Thin, through-coloured | Flexible and tough; less breathable than silicone |
| Lime | Soft, traditional | Highly breathable; suits older solid walls |
Pebbledash, roughcast and dry dash are textured finishes where small stones are thrown onto or mixed into a cement render.
Which render suits your house?
The right render depends mostly on how your walls are built. Modern cavity walls of brick or block suit most render systems, including silicone, acrylic and monocouche. Older solid walls of brick or stone, typical of houses built before around the 1920s, need to let moisture escape, so a breathable lime render is usually the safer choice. Covering an older solid wall with dense cement render can trap moisture and lead to damp inside.
Timber-frame houses and extensions are rendered onto a carrier board with a drained cavity behind, rather than directly onto the frame. Colour and texture also matter: look at the street and, in a conservation area, check what the council will accept.
How is a house rendered?
Rendering a house is mostly preparation, and good preparation decides how long the finish lasts. A typical job runs like this:
- Erect scaffolding and protect windows, doors, paths and plants.
- Remove loose or failed render and repair cracks or damaged brickwork.
- Fit render beads at corners, edges and window reveals, with a bellcast bead above the damp-proof course so render stops short of it.
- Apply a base coat, often with reinforcing mesh, then allow it to cure.
- Apply the top coat and finish it to the chosen texture.
- Refit pipes and fittings, then strike the scaffold and clear up.
Render must not be applied in frost, heavy rain or very low temperatures, and most products need temperatures of at least 5°C, so winter work is limited. A typical house takes one to three weeks, depending on the weather and how many coats are needed.
How much does rendering cost?
Rendering a house typically costs £7,000–£16,000 including VAT, depending on the wall area, scaffolding, the render system and how much preparation the walls need. A single elevation of a small house sits at the lower end, while a whole detached house with silicone render and full scaffolding sits higher.
Costs rise with removing old render or pebbledash, repairing brickwork, extra beads around many windows and bay fronts, three-storey scaffolding, and adding insulation. Painting a sand and cement render is an extra step that through-coloured renders avoid. Our guide-price tool gives a range for your house, and the prices page shows related figures.
Do you need planning permission or Building Regulations approval to render?
Rendering a house does not usually need planning permission, but it often does in a conservation area, on a listed building, or where an Article 4 direction applies. In England, for example, cladding any part of a house in a conservation area with render, stone, timber, plastic or tiles is not permitted development, so an application is needed. Some councils also take the view that rendering a house that is currently brick changes its appearance enough to need permission, so we check before quoting.
Building Regulations can apply too. Re-rendering a large area of wall, or rendering over new insulation, can count as renovating a thermal element, which may mean building control is involved and insulation is added where practical. Our Building Regulations guide explains approvals in each nation.
Can you add insulation when rendering?
Yes. External wall insulation adds insulation boards to the outside of the wall, fixed and finished with mesh and render. It suits solid-walled houses that cannot have cavity wall insulation and can make a real difference to heat loss. It is more involved than render alone: windowsills often need extending, pipes and fittings moving, and the roof edge extending to cover the thicker wall. Because it changes the outside of the house more, planning permission is more likely to be needed.
How long does render last?
A well-applied render on a sound wall typically lasts 20 to 30 years or more, though the figure varies with the product, the exposure of the wall and how well it is maintained. Through-coloured silicone and acrylic renders tend to keep their appearance for longer than painted sand and cement, which usually needs repainting every five to ten years. Lime render, looked after properly, can last for generations.
Render usually fails where water gets behind it, from leaking gutters, failed sills or cracks left unrepaired. Hollow-sounding patches, bulges and staining are signs that it is coming away from the wall and should be checked.
How do you look after a rendered wall?
Rendered walls need little upkeep if gutters and downpipes are kept working, because most render problems start with water running down the wall. Clean through-coloured renders every few years with a gentle wash and a suitable biocide if algae appears, rather than a high-pressure jet. Repaint sand and cement render as the paint wears, using a breathable masonry paint. Fill fine cracks early, and have larger cracks looked at in case they point to movement in the wall.
See our external rendering page for how we approach render on different types of house.
Related services
- External rendering: guide £7,000–£16,000 inc VAT
- Brickwork and repointing: guide £2,500–£6,000 inc VAT
- Painting and decorating: guide £1,200–£3,000 inc VAT
Figures in this guide are typical UK ranges including VAT where it applies. They are not quotes. Rules on planning and building control differ between England, Wales, Scotland and Northern Ireland and change over time, so we check what applies to your property before quoting.