Rendering & EWI, answered.

Rendering in the UK in 2026 costs £40–£130 per m² depending on the system specified. Sand and cement (traditional) is the cheapest at £40–£80/m². Monocouche through-coloured render costs £55–£90/m². Silicone render — the premium choice — costs £70–£120/m². Lime render for heritage and listed properties costs £80–£130/m².

London and South East prices sit 15–25% above national averages due to higher labour and scaffolding rates. All quoted prices include labour, materials, base coat, mesh reinforcement, beading around openings, scaffolding supply, and final finish. Removal of existing render typically adds £25–£40/m² to the total.

Silicone render lasts 25–40 years when correctly installed on properly prepared substrate. It is through-coloured (so no painting is required for its lifespan), self-cleaning due to silicone's hydrophobic properties, highly crack-resistant compared to traditional sand & cement, and vapour-permeable so moisture can escape from the wall.

The leading product, K-Rend Silicone K1, carries BBA certificate 97/3428 and is CE marked to BS EN 998-1:2016. It's NHBC accepted for warrantied new-builds and Kitemarked. Full silicone render London guide →

Both are through-coloured cementitious renders that don't need painting, but they differ in chemistry, performance, and price:

Silicone render contains a silicone admixture that makes the surface hydrophobic (water-repellent and self-cleaning). Lifespan 25–40 years. Costs 15–25% more than monocouche.

Monocouche is a one-coat cementitious render applied at 15–18mm thickness in two passes. Lifespan 25–35 years. More widely used on new-build developments due to faster application.

For exposed or coastal properties, silicone is the right call. For sheltered urban properties, monocouche is perfectly adequate and saves money. Both can be hand-applied or spray-applied.

External Wall Insulation in London costs £90–£200 per m² installed in 2026, depending on insulation type. For a typical 3-bed semi-detached house with approximately 100m² of wall area, expected total costs are:

EPS (expanded polystyrene, most common): £10,625–£15,350
Kingspan / PIR (thinner, higher performance): £14,200–£18,900
Rockwool (mineral wool, non-combustible): £15,350–£20,000
Wood fibre (heritage / eco): £17,700–£23,600

All prices include insulation boards, adhesive, mechanical fixings, fibreglass mesh, base coat, render finish, beading, scaffolding, and the manufacturer's BBA-approved system warranty. London prices include the 18% regional premium.

Yes — EWI typically reduces heating bills by 35% or more on solid-walled properties with no prior insulation. The Energy Saving Trust estimates external wall insulation saves £400–£700 per year on heating for a typical detached home.

Payback periods are usually 8–12 years, depending on energy prices and the starting EPC rating. After payback, the savings are pure gain for the remainder of the system's 30+ year lifespan. EWI also typically lifts an EPC rating by 1–2 bands, which can improve resale value.

K-Rend is the UK's leading silicone render brand, manufactured by Kilwaughter Minerals Limited in Northern Ireland. Their flagship product, K-Rend Silicone K1, is a one-coat polymer-modified cementitious render with silicone admixture, applied at 16–20mm finished thickness.

K-Rend Silicone K1 carries BBA certificate 97/3428 and is CE marked to BS EN 998-1:2016. Other key K-Rend products include K1 Spray (machine-applied), Silicone TC15 (thin-coat system), and LW1 (lightweight render for EPS-based EWI build-ups). All are Kitemarked and accepted by the NHBC. Full K-Rend London guide →

Monocouche render is a one-coat through-coloured cementitious render applied in two passes to achieve 15–18mm finished thickness. The name comes from the French for "single coat" — it eliminates the need for separate base and top coats used in traditional rendering.

The leading UK monocouche systems are Weber weberpral M (BBA cert 17/5464), K-Rend monocouche, and Parex Monorex GM (BBA cert 21/5888). PRB Systems offer a thinner 12mm version. Because the colour is mixed through the render, no painting is required for the system's 25–35 year lifespan. Full monocouche render London guide →

All three are leading UK render system manufacturers, but they specialise differently:

K-Rend (Kilwaughter Minerals, Northern Ireland) specialises in silicone-coloured renders and is the UK's best-known silicone brand. Premium pricing, premium finish.

Weber (Saint-Gobain) offers the broadest range — including monocouche (weberpral M, BBA 17/5464), thin-coat, full EWI systems (weber.therm XM), and mortars. Good for projects that need a one-stop manufacturer for multiple build-ups.

Parex (Sika UK) focuses on high-performance thin-coat and one-coat systems (Monorex GM, BBA 21/5888). Particularly popular on new-build housing developments where consistency across hundreds of plots matters.

All three are BBA-certified manufacturers and we are approved applicators for all three.

Monocouche render typically lasts 25–35 years when installed correctly on a properly prepared substrate. Like silicone render, monocouche is through-coloured, weather-resistant, and requires no painting throughout its lifespan.

Weber's weberpral M, K-Rend monocouche, and Parex Monorex GM all carry BBA certification with NHBC acceptance for warrantied new-build construction, so they're approved for use on homes under structural warranty.

The ECO4 scheme and the Great British Insulation Scheme can fund 25–100% of EWI installation costs for eligible UK households. Some households pay nothing toward the work.

Eligibility is means-tested. Key factors:

— Household income (lower-income households prioritised)
— Benefits received (Universal Credit, Pension Credit, etc.)
— EPC rating (typically band D or below)
— Property type (solid-walled, owner-occupied or private rental)
— Low Income/High Cost (LIHC) area classification

The schemes are administered by approved installers working with qualified retrofit assessors. We recommend checking eligibility through a trusted assessor before committing to any work.

Four main insulation types are used in UK EWI systems:

EPS (expanded polystyrene) — most common, £90–£130/m² installed, U-value ~0.30 W/m²K at 100mm. Lifespan 30+ years.

Kingspan / PIR — thinnest high-performance option, £120–£160/m². U-value ~0.22 W/m²K at 80mm. Useful where build-up depth is restricted.

Rockwool (mineral wool) — non-combustible, £130–£170/m². Required by building regulations on many buildings over 11m. Euroclass A1 fire rating. Excellent acoustic performance.

Wood fibre — natural and breathable, £150–£200/m². Ideal for heritage and solid-wall properties where moisture management matters. Low embodied carbon.

Typical render job timelines, weather permitting:

— Small extension or garden wall: 2–5 days
— 3-bed semi (full external): 1–2 weeks
— 4-bed detached: 2–3 weeks
— Large detached or commercial: 3–5 weeks
— EWI system (full house): 2–4 weeks (longer than render alone)
— New-build development: Coordinated bay-by-bay with main contractor

UK weather is the biggest variable — render needs reasonable temperatures (above 5°C) and dry conditions. Winter jobs may run longer due to delays.

Most rendering and EWI work falls under Permitted Development in the UK and does not need planning permission. However, exceptions apply:

— Conservation areas — often require planning consent for external alterations
— Listed buildings — Listed Building Consent always required
— Flats and maisonettes — generally need planning permission
— Article 4 Direction areas — local council has removed permitted development rights

Always check with your local planning authority before starting work. We can flag potential issues at the site visit but do not handle planning applications ourselves.

Yes — render can be applied directly to clean, sound brickwork. Most systems require a suction-control coat or base coat first (such as Parex Microgobetis 3000 or PRB Fondisol F) to manage how much water the substrate absorbs from the render mix.

Different substrates need different preparation: high-suction substrates like lightweight aircrete or clay blocks always need a primer; dense concrete blocks may need a key coat; older or damaged brickwork needs repair before rendering. A pre-render site survey confirms which preparation is needed.

For a 3-bed semi-detached house in London with approximately 100m² of wall area, expected 2026 costs are:

— Sand & cement: £4,000–£8,000
— Monocouche: £5,500–£9,000
— Silicone render: £7,500–£12,000
— Spray-applied silicone (new-builds): £6,500–£10,000

Prices include scaffolding, materials, labour, base coat, mesh, beading and finish. Adding EWI as well (insulation + render) brings the total to £10,625–£15,350 for an EPS system, or up to £23,600 for premium wood fibre.

For new-build developments, monocouche and thin-coat silicone are the most commonly specified systems. Weber weberpral M, K-Rend monocouche, Parex Monorex GM, and PRB monocouche are widely used.

Spray application is preferred on large new-build schemes because it cuts time on site by 30–40% and produces a more uniform finish across hundreds of square metres. All major manufacturers (K-Rend, Weber, Parex) offer spray-grade versions.

Bulk new-build pricing is typically £55–£85/m² installed — lower per m² than one-off residential due to scale and shared main contractor scaffolding.

Linx Render is an approved applicator for six BBA-certified manufacturer systems:

— K-Rend (BBA 97/3428)
— Weber (BBA 17/5464)
— Parex / Sika (BBA 21/5888, NSAI 05/0219)
— Sto (BBA 95/3132)
— PRB Systems (BBA on key monocouches, Pro Contractor status)
— Wetherby Wall Systems (part of ROCKWOOL Group, BOPAS 60-year durability certification, KIWA/BDA accredited)

BBA approval applies to the manufacturer's products; "approved applicator" status means we are trained and audited by each manufacturer to install their systems correctly so that the BBA-backed warranty remains valid. Full specifications and datasheets.