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Advice on external wall insulation

We can advise on a range of government grant schemes, and provide guidance on insulation designs and what planning permission is required.

Planning permission is required in most cases, particularly when the insulation is to a side of your property that is visible from the street.

In listed buildings and conservation areas, where extra controls apply, we need to carry out a careful assessment of proposals for external wall insulation to see whether they are appropriate.

If you install external wall insulation without applying for planning permission there is a risk that the council will ask you to remove it.

Benefits of external wall insulation

External wall insulation is an effective way to keep your home warm. It is often preferred over internal wall insulation because it's simpler to install and you won’t need to redecorate afterwards. Up to 35% of heat can be lost from poorly insulated walls.

  • Protect your home from heat loss.
  • External wall insulation can reduce your fuel bills by as much as 25%.
  • Lower your carbon footprint.

Find out if you are eligible for grants

Use the government website to see if you are eligible for any grants for external wall insulation or other energy efficiency measures:

Follow the questionnaire from “Start”. It will ask you details about your property and give you useful links at the end.

How do I find an installer?

Installers providing external wall insulation under a government grant must be TrustMark registered. You can find a registered installer on the TrustMark website.

If you are approached by a company

You might be approached by a company offering installation under a grant, usually by a lead generator, then a retrofit assessor and then by the installer. We recommend that you:

  1. ask for the installer’s company details and ask to see their ID whenever they visit you
  2. make sure they leave you their name, address and telephone number in case you want to check on the status of your application after they leave. We will not have access to this information.

Get agreements in writing

We recommend that anything agreed about the work is put in writing. Even if you are not paying towards the work, you should have a written contract which contains the right to cancel. If you need to contribute towards the cost of the work, do not pay until the work is complete.

We also recommend:

  • paying by credit card as this will provide extra protection if things go wrong
  • asking assessors and installers how they will reinstall guttering, pipes, cabling and satellite dishes
  • that you consider any shared services, access ways or guttering you might have with your neighbours and how your new insulation might affect their property.

Your neighbours

In some cases your neighbours might need to sign an agreement before the work is done to avoid any legal or civil disputes after installation - this is known as a party wall agreement. Find more information at Party walls and building work - GOV.UK.

Get in touch for advice

We recommend that you email both these teams for advice before committing to installation.

The planning team will seek to ensure that works reflect the existing street scene (including terraced properties with distinctive original features). Installation should not result in the loss of attractive or original features. We can advise on how to avoid this.

Check if you need building control approval

You should also check if you need building control approval for the installation of external wall insulation. Your installer may not need to get approval if they are registered with a competent person scheme. More guidance can be found at Competent person scheme - GOV.UK.

Report a scam

We are aware that there may be unregistered companies installing external wall insulation, without planning permission and often to a poor standard.

If you believe that you have been a victim of a scam, contact Citizens Advice Consumer Service using the details below. Make sure you have as many details as possible, including any details of the company that has installed the insulation, photos and dates.

  • Call: 0808 223 1133 (Citizens Advice Consumer Service will report to our Trading Standards team).

You can also contact the TrustMark complaints scheme.

Further advice and information