How is External Wall Insulation Installed?

External Wall Insulation, otherwise known as External Façade Improvement (EFI) is the process of insulating your home by installing a layer of wall insulation material which is fixed to the exterior wall which is designed to protect and insulate. This layer is then covered with reinforcement and a special type of render, then completed to a high standard with a finish of your choice.

Choosing your External Wall Insulation finish is important to make sure you get the perfect look for your home. To help you decide, Nesture has an external wall insulation tool, to show you what your home will look like once the project is complete. You can choose from a variety of finishes for an attractive finish including render, pebble dash, brick slip or brick effect render.

External Wall Insulation has several benefits; however, it can change the external appearance of your home. If you are unsure then it is best to check with your local planning authority whether you will need planning permission, our customer support team can also provide help and advice.

The most common restrictions for External Wall Insulation are on listed buildings or if your home is in an area of conservation. If you want to install External Wall Insulation to more than 25% of your walls, then you will need to make sure they are up to current standards. This will aid the installation process. You must also ensure that the thermal performance of the insulated wall has a U-value of no more than 0.30.

Hover or click the numbers below for an explanation of each layer

  • 1

    Base Track & Insulation boards

    These are the insulation boards which are attached to your walls.

  • 2

    Base Coat

    This is a render upon which a variety of other finishes or finishing coats may be applied.

  • 3


    The reinforcement mesh helps to stop the render cracking and strengthens the system.

  • 4

    Thin Base Coat

    This is to cover the mesh.

  • 5

    Top Coat

    There are a range of top coats which can be applied such as a Silicone / Acrylic finish, an Enviromin coat, pebble dash, brick slip or brick render effect.


The Installation Process

We have outlined the steps below involved in the installation process of External Wall Insulation.

Frequently Asked Questions

How long does External Wall Insulation Installation Take? Do I need to be present?

The length of time taken to install External Wall Insulation will depend on the size of your home but, as a guide, a typical 3-bedroom semi-detached house will take approximately 3-4 weeks from assembly to the dismantling of the scaffolding.  This will include preparatory works such as extending flues and overflow pipes and reinstating the rain water pipes. You will not need to be present during the application of the External Wall Insulation system, as all of the works will be carried out to the exterior of the building and access to the inside of your property is not generally required except at two stages when we need to enable the plumbing and electrics.

View all FAQs


Get a FREE Quote

For a FREE quote from a survey, please complete the form below.

I am interested in External Wall Insulation because it can -

We guarantee 100% privacy. Your information will not be shared.