Cavity wall insulation
Good cavity wall insulation can cut your heat loss by up to 33%; and cut your energy bills by up to £420 a year(1)
Find out more about cavity wall insulation – and see if you're eligible for funding to help you with the cost of cavity wall insulation.
Get help to insulate your home
Do you live in a home with a low Energy Performace Certificate (EPC) rating? It's worth checking to see if you can get funding to insulate your home. There are a couple of schemes available to our customers:
ECO4 – eligible customers can get a package of free energy efficiency measures to improve their home's EPC rating
All about cavity wall insulation
What is cavity wall insulation?
Cavity wall insulation is one of the best and most affordable ways to improve your home's energy efficiency. It can last up to 42 years.
A cavity wall is made of two layers with a gap or ‘cavity’ between them. Insulation can be injected into the cavity through drill holes in the outside walls. Insulation is usually mineral wool or polystyrene beads, or polyurethane foam.
If your home was built after the 1920s, it's likely to have cavity wall (rather than a solid wall, which has no cavities to fill).
How can I tell if I have a cavity wall?
There are some common ways to tell if your property has a cavity wall:
- It was built after 1920; homes built within the last 40 years almost certainly do
- It has walls more than 260mm thick
- It has a brickwork pattern like one of the picture examples shown below
If your home was built before the 1920s, it's likely the external walls are solid walls.Solid walls have no gap, so they can’t be filled with cavity wall insulation.
Cavity wall brick patterns
Why is cavity wall insulation a good idea?
Insulating the cavity space between the outside and inside wall adds a barrier to stop the cold from coming in and heat from escaping.
Save up to £420 on energy bills(1)
Less heat escaping means less energy used to heat your home, saving you money.
Better for the planet
Wasting less energy to heat your home, means your carbon emissions will drop
Better EPC rating
Your home will be more energy-efficient and more attractive to buyers
Reduce heat loss
Keep your home warmer using less energy
What our customers say
I have noticed a huge difference in the warmth of my home. Before I was having the heating on not just high during the day but also I had to keep it on through the evening during very cold winter nights. This was extremely expensive.
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