Local EWI & Rendering Installers
External Wall Insulation in Harrow
Insured, TrustMark-registered installers of external wall insulation and silicone render, working across Harrow, Pinner, Stanmore, Wealdstone and Wembley. Clear pricing, tidy workmanship and a guarantee of up to 25 years.
Why Harrow homes benefit from external wall insulation
Harrow is classic 1930s “Metroland”: street after street of semi-detached homes in Rayners Lane, Kenton, Wealdstone and North Harrow, plus Victorian terraces around Harrow on the Hill. These homes were built long before wall insulation existed – solid or poorly filled walls make them expensive to heat and prone to condensation.
An insulated render system wraps the outside of the house in EPS, Rockwool or Kingspan boards and finishes it with a durable silicone, scratch, brick-effect or pebble dash render. The result: warmer rooms, lower bills, protected brickwork and a fresh, modern façade – without losing any interior space.
Our Work Near You
Recent projects near Harrow
How much does external wall insulation cost in Harrow?
As a guide, our insulated render systems start from £120/m² for EPS, £140/m² for Rockwool and £135/m² for Kingspan, including the render finish. A typical three-bed semi with around 100 m² of external wall usually comes to roughly £12,000–£14,000 depending on the material, access and detailing. Every quote is free, written and itemised – try our cost calculator or book a free survey.
Harrow EWI questions, answered
Do I need planning permission for external wall insulation in Harrow?
In most cases no – EWI usually falls under permitted development. Where consent is needed, the local authority is Harrow Council. Harrow on the Hill is a conservation area, so we always check before we start – it’s included in the free survey.
How long does an EWI installation take?
A typical semi takes 5–10 working days including scaffolding, boarding, rendering and finishing. We protect driveways and gardens and tidy the site every day.
Which areas around Harrow do you cover?
We cover Rayners Lane, Kenton, Wealdstone, North Harrow, South Harrow and Harrow on the Hill, plus Pinner, Stanmore, Edgware, Ruislip and Wembley.
What guarantee do I get?
Every installation comes with a written workmanship warranty, with insurance-backed cover of up to 25 years available for complete peace of mind.
Get your free Harrow quote
Tell us about your property and we’ll come back the same working day. Or call 020 4542 3074.