Can I get cavity wall insulation for my flat?

Can you get cavity wall insulation if you live in a flat?

It is an often asked question at Green Deal Assessments, but the answer is not really straight forward. You live in a flat or maisonette, it has cavity walls, and you want it insulated to help cut your bills. What can you do?

Well, first of all, you can’t simply get insulation like someone that owns the whole house. There are other people who share those walls with you, which means there are going to be lots of other considerations. The insulation will be in their wall too.

Here are some of the most commonly asked questions and our answers, to dispel some of the myths and help you arrange insulation for your flats.

Can I get cavity wall insulation on just one bit of the property?

Generally, cavity wall insulation must be done over the whole property. In some cases however, where the concrete floor of the flats extends into the cavity, it may be possible to insulate just one flat.

Do I need permission from the other residents to get the insulation?

Unless you can just insulate your property alone, you will have to insulate the whole wall and all leaseholders/flat owners will need to agree to the work being carried out.

What if it is a council property?

Some councils have already looked at insulating their housing stock, so you may have already been examined. Each council is different however, so it is worth checking your council’s website or giving them a call to see if they have a scheme in place

What do I do if there are a mixture of council and private tenants?

Once again, you will need to speak to the council, as they will let you know whether you can go ahead and privately insulate the block. The council may help contribute towards the costs, but it will depend on the council in question. For private tenants, the landlord will have to agree to the installation.

One of the residents doesn’t want the insulation, and refuses point blank to consider it, what can I do?

Unfortunately there isn’t too much you can do. If they are an owner occupier or landlord it is up to them what is done to their property. If they are a council tenant, you can put some pressure on the council to get the insulation done. Either way, it is going to be a difficult job to get done. We suggest trying to deal with their concerns and convince them that it is the best course of action.

Does it matter how big the property is?

Usually, any property below 25 meters can be cavity insulated using traditional methods, although the taller it is, the more expensive the installation. In special cases, independent certification bodies have approved cavity wall insulation in walls above 25 metres in height. Each project has to be assessed by the certification body for suitability before approval is given.

How much will it cost, and is it more than insulating a house?

Obviously if you are getting the insulation between all the members of the flat, you will be able to split the costs between you. As such it could prove to be a little cheaper per flat than getting it done for an individual house.

Can I get the insulation under the Green Deal?

Yes and no. Technically, there is no reason why you couldn’t split repayments over all the properties, but practically it may prove difficult. Each property would need its own Green Deal Assessment and it will then be down to the Provider and Installer as to whether they go ahead with the installation.

Can I get the insulation under ECO (the Energy Company Obligation)?

Potentially yes. If your property falls in a CSCO postcode you could potentially get the insulation for free or at a much reduced cost. Unfortunately there is no funding for ‘hard to treat’ cavity walls (i.e. 3 stories or more) so you are only likely to get funding for straight forward low rise properties.

So you can see why most blocks of flats have not been insulated. It is likely going to need someone such as yourself to get the ball rolling and convince your fellow residents to make the installation happen, but it really is worthwhile if you can get them to agree.

If you would like to read more about cavity wall insulation, see our full guide here.


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