It isn't just cavity walls that need some care and attention. Heat escapes through solid walls too, so the government's Energy Companies Obligation (ECO) scheme provides free internal wall insulation and internal wall insulation grants.
You can get a lot more information about external wall insulation from us, but on this page, we're concentrating on internal wall insulation.
First off, why would you choose internal wall insulation? There are a few good reasons:
The cost of internal wall insulation is around half the cost of external wall insulation (at about £40/m² and £50/m²) so that could be a factor if you need to pay for some of the work yourself.According to the Energy Saving Trust, you can expect to see savings of around £455 on your annual heating bills. Internal wall insulation is a better option if you don't want to change the look of your building externally.
Inevitably, you will sacrifice a little bit of space inside your property, but by the time the work is done and dusted you'll hardly notice. You will notice the extra heat though. After all, that's what the internal wall insulation grants are all about. Your newly insulated home will retain a lot more heat, so you can turn your thermostat down and see the savings stack up without feeling any less warm and cosy.
Is your wall suitable for free internal wall insulation?
You will need to make sure your wall is in suitable condition. For example, if your plaster is in poor condition, or if it will not support an adhesive, it may need to be removed. It is important to create a nice airtight seal to prevent as much heat escaping as possible, so you might also need to consider making additional improvements to floor voids or cracks.
If your wall suffers major damp problems, you might also want to try and address that issue first. You should also tell the company carrying out the work so they can factor it in when deciding on the best option for your home.
There are three main types of internal wall insulation methods:
- Rigid foam boards (like Kingspan or Celotex) - good insulators and take up less room than the alternatives.
- Mineral wools (Rockwool or Knauf) - tend to be cheaper than foam boards.
- Natural materials (e.g. sheep’s wool, woodfibre or cork) - the eco-friendly option.
The most common method for internal wall insulation involves constructing a new stud wall with a cavity which can then be filled with the chosen internal wall insulation material. When it is all finished, you will have a continuous uninterrupted thermal barrier.
If you are eligible for an internal wall insulation grant, or even free internal insulation, then it really is worth finding out more. It will certainly save you a lot of money on your annual heating bill.
Alternatively, the boards may be glued directly onto the wall with a special adhesive, and additional screws if required. (They may also be battened onto the wall.) Any gaps at the floor or ceiling will be filled and taped over before the plaster-skimming stage of the process. Do be aware that it may not be appropriate to hang heavy items onto the new internal wall - but you can ask your insulation team for their advice.