Many of us here in the UK are interested in the idea of External Wall Insulation, with a vast range of benefits both environmental and financial it is easy to understand why. The biggest reservation many people have is regarding the upfront cost of the External Wall Insulation installation process. In today’s blog, I will explain the costs and hopefully put your financial worries to rest!


The process of External Wall Insulation has many components; the price accounts for the required insulation materials and labour costs. The cost of EWI materials will depend on the size of the project but also what EWI materials you choose. Not only do the prices of materials vary, but some materials require fixings and some require adhesive which will also need to be accounted for within the price. This means that the cost of your EWI system will depend entirely on the specific needs of your project.


Calculating the cost of the External Wall Insulation Materials

As explained above, there are a lot of components to consider when calculating the price. Luckily, we have a great solution for you; not only do we have a fantastic team on hand who can provide you with a quote, but we also have an easy-to-use EWI Materials Calculator tool that takes all of the faffs out of the calculation process. If you would rather have a helping hand and some guidance, just give us a call on 02033974067.


What is the EWI Materials Calculator?

The EWI Materials Calculator is an online tool that enables homeowners, installers and architects to quickly and accurately calculate the correct EWI materials needed to meet their requirements for their next project. The calculator will ask a series of questions to gather how much the system will cost depending on your needs.

Average External Wall Insulation costs:

EWI Typical Cost
Mid-terrace house £4,000 – £6,000
Semi-detached house £8,000 – £10,000
Detached house £12,000 – £14,000 +


This may seem like a scary amount for some but if your property has solid walls, you could save between £115 and £360 a year by installing External Wall Insulation. This means, over time, the External Wall Insulation will start to pay for itself. You have to remember that not only will you save on your heating costs, but you will also reduce the amount of CO2 emissions your property emits into the atmosphere which will help the environment. Your External Wall Insulation job will also be finished with your choice of render and colour, providing additional value if your brickwork is damaged, worn down and in need of a makeover.

If this still sounds like too much for you, there is government-backed support that you could be eligible for. Currently, there is a subsidy called the Energy Company Obligation (ECO) which was launched in December of 2018. The scheme runs until the 31st March 2022 and focuses on customers with low incomes and considered to be in vulnerable situations e.g. living in fuel poverty. Under ECO, grants are available to cover all or part of the cost of energy efficiency measures. Ask your energy provider for more information on this scheme.

Trade Installers get fantastic prices and warranties on the system

As an installer, you may well be eligible for our trade discount prices too; so, not only will you get a BBA-approved external wall insulation system delivered directly to the site, but also the materials you need at a great price. As a trade partner, we are also able to offer system warranties provided the installers have been on our free training course. Be sure to sign up to our Trade Account for free to receive your discounts!

So, there you have it – if you need some help calculating the material requirements for an EWI job, give us a call or use our EWI Materials Calculator today!


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