External wall insulation cost in North London
As a guide, external wall insulation costs around £90 to £150 per square metre, and a whole house is often somewhere between £8,000 and £20,000. These are guide figures, not fixed quotes, because the real price depends on your walls, the render finish and access. Kev Construct Ltd gives free, honest estimates.
Recent EWI projects
How much does external wall insulation cost?
As a rough guide, most EWI work falls around £90 to £150 per square metre of wall covered, including insulation, base coat and render finish. For a typical house, that often works out at somewhere between £8,000 and £20,000 for the whole property.
Guide figures for North London, 2026 - not fixed quotes. Every project is quoted individually after a free site visit, and the final figure goes in writing with no hidden fees before any work begins.
What affects the cost of EWI?
Please treat the figures above as guides only. A small mid-terrace with simple walls sits at the lower end, while a large detached home with lots of detailing sits higher. Several practical things move the price up or down, and it helps to understand them before you compare quotes:
- Wall area, which is the biggest single factor, since more square metres means more material and labour
- The type and thickness of insulation needed to reach the performance you want
- The render finish you choose, with silicone render typically costing more than basic options but offering flexibility, crack resistance and self-cleaning
- Access, because scaffolding and hard-to-reach walls add time and cost
- The condition of your walls, and any repairs or damp treatment needed first
- Detailing around windows, doors, pipes and features, which takes extra care
A good quote spells these out, so you can see exactly what is included rather than guessing.
Is external wall insulation worth the cost?
For many North London homes, yes. EWI is one of the few upgrades that pays you back on several fronts. You get a warmer home and lower energy bills year after year, a smarter render finish that lifts the whole property, and added value and kerb appeal. On top of that, your walls are better protected from the weather, which can reduce damp and future repair costs.
For families weighing up the cost of moving against the cost of improving, EWI is often a sensible investment that makes the home you already have far nicer to live in.
How to get an accurate EWI price
Online guide figures are useful for planning, but only a proper visit gives you a real number. When we come out, we measure your walls, discuss the finish you want, check access and note any repairs needed. You then receive a clear written quote from Marian with no hidden fees, so the price you agree is the price you pay unless you ask us to change the scope.
Good to know.
How much does external wall insulation cost for a whole house?
As a guide, whole-house EWI often costs somewhere between £8,000 and £20,000, based on roughly £90 to £150 per square metre. Smaller terraced homes tend toward the lower end and larger detached homes toward the higher end. A free site visit gives you an accurate figure for your property.
Why do EWI quotes vary so much?
Because homes vary so much. Wall area, insulation thickness, render choice, access and the condition of your walls all affect the price. A cheap quote may leave out preparation, scaffolding or proper detailing, so always compare what is actually included, not just the headline number. Our quotes set this out clearly.
Are there grants for external wall insulation?
Government schemes for insulation come and go and have eligibility rules, so availability changes over time. We do not manage grant applications, but we are happy to give you a clear quote you can use when checking any scheme you may qualify for. It is worth researching current schemes before you start.
Is the guide price the same as my final quote?
No. The £90 to £150 per square metre and £8,000 to £20,000 figures are guides to help you plan. Your final quote comes after a free site visit, where we measure and assess your home, so it reflects your actual walls, finish and access.
Get your free EWI
cost estimate
For a clear, no-obligation price based on your home, book a free estimate today. You'll get a fixed price in writing - with no hidden fees.
- Free home visit & survey
- Fixed price in writing - no surprises
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