Get cavity wall insulation

Looking for an affordable way to cut your energy bills and keep your home nice and cosy? Let us put you in touch with a qualified cavity wall insulation installer.

Good cavity wall insulation can cut your heat loss by up to 33% – and your energy bills by up to £255 a year(1).

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Cavity wall insulation - Installing cavity wall insulation

What is cavity wall insulation?

Cavity wall insulation is one of the best and affordable ways you can do to improve your home's energy efficiency.

Houses in the UK mostly have either cavity walls or solid walls:

  • Cavity walls are made of two layers with a gap or ‘cavity’ between them. If your home was built after the 1920s, it's likely to have cavity wall
     
  • Solid walls have no gap, so they can’t be filled with cavity wall insulation. If your home was built before the 1920s, it's likely the external walls are solid walls rather than cavity walls


Cavity walls can be insulated by injecting insulation into the cavity from the outside through drill holes in the outside walls. Insulation is usually mineral wool or polystyrene beads or polyurethane foam.

For a typical home, cavity wall insulation starts from £950. 

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Cavity wall brick pattern example 1
  • Cavity wall brick pattern example 1
Cavity wall brick pattern example 2
  • Cavity wall brick pattern example 2
Cavity wall brick pattern example 4
  • Cavity wall brick pattern example 4
Cavity wall brick pattern example 3
  • Cavity wall brick pattern example 3

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 brickwork like one of these picture examples
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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 £255 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

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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.

Mr H, Kingston

There's other insulation to consider

thermal loft insulation roll

Loft insulation

from £800 professionally installed

Save up to £315 on bills and prevent 25% of your heat loss through your roof(2)

Get loft insulation

Insulation and energy-saving advice

floor insulation under concrete

A Complete Guide to Floor Insulation

Cold doesn't just come in through walls, doors and windows, it can come up through the floor too. Insulation can prevent this, make the floor more comfortable to walk on and prevent mould.

Learn about floor insulation
group of friends in a conservatory

Conservatory Insulation: Use it All Year Round

Conservatories are often considered a room used in summer but with proper insulation, it could be used all year round.

Learn about conservatory insulation
cavity wall cross section into a home interior

How insulation works

Get into the details of how insulation can save you money, energy and CO2 emissions, and what different types of insulation there are out there and the materials used.

Learn how insulation works