How Do I Choose a Reputable Company For External Wall Insulation?

non standard house advice, non straditional construction advice

Hello, I’ve been a long time lurker here and I have found this website to be an amazing source of information and inspiration over the past few years.
I have been reading the articles on the Green Deal with great interest.

The increase in available funds is a fantastic boost for all of us who own bisf homes and I’m very keen to get started with my house and perhaps involve others in my street.

I have spoken to a couple of companies who I won’t name at this stage but I have found that the their quotes vary wildly for the work, meaning more cash input from me.
To be honest, I don’t want to have to pay anymore than what I have to, otherwise once again it will simply be too expensive to even consider.

My question is, how do I choose a good reputable company who is familiar with my house type whilst at the same time keep the cash differnce that I have to pay toward the project as low as possible?
Also how do I know if the company is any good? Some show me flashy brochures but it doesnt show my house type.

Any help would be brilliant.

Oh and keep up the amazing work everyone!


  1. Hello AnneB
    The warmest of welcomes to our community.
    There are some exciting changes taking place as we speak at the moment. particularly relating to the Green Deal and the new Green Deal Home Improvement Fund or GDHIF.

    Never before has such a golden opportunity been available to owners of BISF Houses or indeed owners of any other property that has solid walls, or walls without a traditional cavity.

    We always recommend choosing a company that is familiar with BISF construction as there are a number of considerations that are specific to this house type, that require the application of knowledge and specialised skill in order to ensure that the installation is safe, secure and certifiable under the conditions of the Green Deal scheme.

    The obvious starting point is to ensure that you employ an authorised Green Deal Installer. You can use our handy search tool to obtain a list of installers that cover your region on our EWI installers page

    The next step would be to contact several companies and actually ask them if they have fitted EWI to BISF Houses before and if so, do they have any examples for you to view.

    During our recent telephone poll of Green Deal installers, we found that only around 30% of companies were familiar with BISF construction. This would indicate that you may have to contact several companies during your search.

    Primarily if you have already been Greed Deal Assessed, your next step is to obtain quotes from installers as this will determine how much of your own cash you need to provide. You should obtain at least three quotes and never ever settle for the first quote that you are given. You also need to establish what type of insulation system that they propose to use and what choices you have, relating to the colour and finish. After all, it will be you that will be looking at it every day, so you need to be happy with your choice. Remember, some render systems are actually pre-coloured and not designed to be over painted like traditional render is.

    As for prices, asking any installer to quote for installing EWI to just a single property, will undoubtedly result in you being supplied with a high quote but if you are able to persuade several neighbours to also take part in the scheme, you could find that you could reduce the cost considerably. Typically, we would suggest involving 5 or more neighbours if possible.

    The reason why your quote should be cheaper, is simply down to logistics, labour, materials and set up costs etc. It is more cost effective for an installer to work on 5-10 houses together than one just one house on its own. Reduced operating costs allows this saving to be passed on to you by way of a more competitive quotation for the group.

    We hope to write more about resident group installations in the near future.