5 benefits of external wall insulation

Benefits of external wall insulation

22 million homes in the UK have been identified as requiring upgrades in order to reduce wasted energy. 8.5 million of those homes are rated as ‘hard to treat’, meaning usual methods of retroactively insulating, such as cavity wall insulation, aren’t always an option.

External wall insulation (EWI) makes it possible to insulate a home by fitting insulation to the outside of the property, improving thermal performance, reducing energy consumption — therefore lowering energy bills — and updating the aesthetics.

EWI systems are built up in several layers. The insulation board itself can be any one of a number of options which are each suited to different projects and their requirements. You can find an in-depth look at the options here.

After fixing the boards to the wall, the system is built up using multiple coats which will include:

  • Render
  • Reinforcement mesh
  • Primer
  • Decorative finish or top coat render

You can even choose a brick-effect finish, so you can keep the traditional character of your property.

Since all the work takes place outside, there’s no need to move out during the renovation work. Choosing EWI also avoids interfering with plumbing and electrics and means space inside the home is not impacted, unlike with internal insulation which can reduce the inside space by up to 7%.

Here are 5 benefits of choosing external wall insulation for your project:

  • EWI thermal performance icon

    1. Improves the thermal performance of a building

    EWI improves the walls’ thermal inertia and limits heat loss. This improves the indoor thermal comfort, reduces heating costs, and limits CO pollution.

  • More comfortable temperature icon

    2. Living spaces become more comfortable

    Heat loss through the walls of a home causes damp, which can lead to the degrading of paint and plaster, wallpaper coming unstuck, and potentially, the development of mould. Even worse, damp found inside the home can also contribute to respiratory problems. Having a properly insulated home limits the effects of condensation, and can help tackle issues with damp. Your home will be cooler in the summer, and warmer in the winter – a win-win.

  • EWI for soundproofing icon

    3. Reduces noise levels

    Noise pollution can be bad for our health and well-being. One way to cut down on disturbances such as traffic noise from outside is to install an EWI system – a quieter home is a more comfortable one.

  • House icon

    4. Makes a more attractive home

    Adding EWI to your home is also a great excuse to rejuvenate its appearance.

    We offer a wide range of low-maintenance and durable decorative finishes. If you decide to go for a painted finished there are over 100 unique colours o
    n offer. For a more traditional look we can offer brick-effect finishes, or if you’re looking for a particularly robust finish we’ve got pebble dash in a range of colour options. We can also offer mineral renders, which can be used to create an array of architectural details such as quoins and ashlars.

  • Find a contractor

    5. A more valuable, high-performance build

    When renovating your home, it’s important to consider the long-term impact on the value of your property. Not only will potential future buyers will be interested in the appearance of the home, but will be delighted to hear that it’s energy efficient and has low heating costs. Investing in your home will pay off in the long-run, as a well-insulated and thermally-efficient house is more attractive to potential buyers.

We Care

If you think EWI is the right choice for you, we can help you find the right contractor for the job. Get in touch with us and we’ll connect you with your local Weber Recommended Applicator. You can also explore our EWI case studies here – to really get a feel for what the finished product will be.

Still have questions?

We’re here to help. You can get in contact by:


Click Compare to help you choose the right product for your project, if you need further assistance please email technical@netweber.co.uk