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How much does external wall insulation cost in the UK?

External wall insulation costs £90 to £160 in the UK, typically around £120 per m². What moves the price most is total wall area in square metres, so a simpler job sits near the bottom of that range and a larger or higher-spec one near the top. Prices reviewed June 2026.

External wall insulation fixes insulation boards to the outside of the house and renders over them. It is priced by the wall area in square metres, and it is the main option for solid-wall homes with no cavity.

From
£90
Typical
£120
Up to
£160
per m² · reviewed June 2026 1 to 3 weeks

External wall insulation cost calculator

Use the calculator to price your external wall insulation in 2026. Adjust the options and area for a UK cost range. Nothing is sent anywhere.

External wall insulation cost breakdown

Typical external wall insulation costs, by the unit:

WhatTypical UK cost
Per m², supplied and fitted£90 to £160 per m²
+ Brick-slip finish (not render)add £30 to £70 per m²
45 m²£4,050 to £7,200
90 m² (typical)£8,100 to £14,400
180 m²£16,200 to £28,800

What's included in the price?

Typical external wall insulation prices include:

What changes the price?

The things that move external wall insulation prices most:

01

Total wall area in square metres

02

Insulation thickness and the finish, render or brick-slip

03

Scaffolding and access

04

Detailing around windows, doors and the roofline

How the price is built up

The price starts from the rate per square metre, £90 to £160, so the total tracks the wall area first. On top of that sit the fixed jobs that come with almost any external wall insulation, the scaffolding and access to reach the upper walls, and the detailing around windows, doors and the roofline where beads, sills and trims all take time. The finish then moves the figure: a rendered finish sits nearer the middle of the band, around £120 per m², while a brick-slip finish instead of render adds £30 to £70 per m² and pushes a job towards the £160 top. Insulation thickness and awkward access lift it further. Labour is usually the larger share on external wall insulation, roughly 55 to 65 percent of the total, with the boards, adhesive, render or brick-slips and trims making up the rest. A brick-slip finish tilts the split back towards materials.

Ways to keep the cost down

Does where you live change the cost?

In London, external wall insulation typically costs around £160 per m², about 30% above the UK average of £120. In the North, Scotland and Wales the guide figure is nearer £110.

RegionFromTypicalUp to
Midlands / East (UK average)£90£120£160
London£120£160£210
South East / South West£100£140£180
North / Scotland / Wales£85£110£150

Guide prices per m², scaled with the same regional multipliers as the calculator. Not quotes.

External wall insulation cost in major UK cities

CityFromTypicalUp to
Belfast£75£100£140
Birmingham£90£120£160
Bristol£100£130£180
Cardiff£85£110£150
Edinburgh£90£120£160
Glasgow£80£110£140
Leeds£85£110£150
Liverpool£85£110£150
London£120£160£210
Manchester£85£120£150
Newcastle£80£110£140
Sheffield£85£110£150

City guide estimates, scaled by local labour costs. Indicative averages for external wall insulation, not quotes.

Grants can cover part of the cost for eligible homes.

Common questions

How much does external wall insulation cost for a house?

At roughly £90 to £160 per square metre, a typical semi works out around £8,000 to £14,000, more for a larger or detached house. Grants can reduce this for eligible homes.

Is external wall insulation worth it?

For a solid-wall home with no cavity it is one of the few ways to insulate the walls and can make a real difference to warmth and bills. It is a significant cost, so check for grants first.

Why is external wall insulation so expensive?

Because it is really three jobs in one: scaffolding the house, fixing an insulation system to every external wall, and then re-rendering the lot, with careful detailing around windows, eaves and pipes. At £90 to £160 per m² a typical house comes to £8,000 to £14,000 or more. It transforms solid-walled homes that have no cavity to fill, which is exactly where it is worth the money.

Do I need planning permission for external wall insulation?

Usually not on a standard house where the appearance stays similar, but conservation areas, listed buildings and flats are common exceptions, and the thicker walls can complicate boundaries on terraces. Building regulations always apply, covering both the insulation standard and the render finish, so use an installer who handles the sign-off.

Can I get external wall insulation for free or funded?

Sometimes, yes. Grants for eligible homes can cover part or occasionally all of the cost, which is significant on a job priced at £90 to £160 per m². Eligibility usually depends on income, benefits or the property's energy rating, and free offers tend to use a standard rendered system rather than a brick-slip finish. Check what you qualify for before paying, because the funded route can remove most of the upfront figure.

Can I fit external wall insulation myself?

It is not really a DIY job. The boards, adhesive and mesh have to go on flat and the render or brick-slip finish needs a skilled hand, or it cracks and lets water in. You also need scaffolding to reach the upper walls safely. Doing it yourself saves the labour share, roughly 55 to 65 percent of the total, but a poor finish costs more to put right, and a botched job can void any grant or warranty.

Does a rendered or brick-slip finish change the price much?

Yes, the finish is one of the bigger swings. A rendered finish sits nearer the middle of the band, around £120 per m². Choosing a brick-slip finish instead of render adds £30 to £70 per m² on top, because the slips cost more and take longer to lay. On a full house that difference runs into thousands, so it is worth deciding early rather than at quote stage.

Official guidance and sources

The rules and schemes referenced on this page come from these official UK sources. The price figures are Costwise's own; see how we price.

These are independent guide prices based on typical UK jobs in 2026. Your actual cost depends on your property, spec, access and where you live. Always get at least three written quotes before committing.

Ready for real numbers?

Compare quotes for your external wall insulation from vetted local pros on Bark. Tell them about the job and they come back to you with prices, so you can check them against the guide here. Free, no obligation.

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