Cavity Wall Insulation
Cavity wall insulation is one of the most effective ways to prevent heat loss and lower your energy bills
Get an instant quote35%
The percentage of heat that escapes through your exterior walls
£225
Annual reduction in energy costs after installing cavity wall insulation (detached gas heated)
5 yrs
The length of time it takes to get your money back after installation
1120kg
Annual reduction in carbon emissions for a detached gas heated property
Cavity Wall Insulation
Over a third of all the heat lost in an uninsulated home escapes through the walls. Cavity wall insulation lowers your energy costs and helps reduce harmful emissions being released into the environment
What is cavity wall insulation?
Insulating material which is placed in the gap between the inner and outer bricks of your property, making it more energy-efficient.
Why should I have CWI installed?
CWI provides a thermal barrier that stops heat escaping through your walls. This makes it easier to maintain a comfortable temperature in your living space.
What are the benefits?
Insulating your walls can reduce your energy bills by up to 1/3 whilst increased energy-efficiency helps lower your impact on the environment.
How is the work carried out?
First we have to find out if your property has cavity walls. This will be determined through a home survey. A cavity wall is made up of two walls with a gap in between, known as the cavity; the outer leaf is usually made of brick, and the inner layer of brick or concrete block.
Home survey
An energy efficiency surveyor will visit your home and look inside your walls with specialised equipment. He will record additional information about your property and measure the amount of insulation required.
Installing your wall insulation
To insulate your cavity walls, the installer drills small holes around 22mm in size at intervals of around 1m in the outside wall of your home. The installer then inserts the insulation into the wall cavity using special equipment.
Finishing the job
The installer will check to see if your walls have the correct amount of insulation. Any holes that have been drilled will be filled with cement or render that matches your property.
Cavity Wall Insulation – Product Information
Our preferred insulating material is a bonded EPS bead system due to its durability, low thermal conductivity and moisture resistance.
What is Expanded Polystyrene (EPS)?
Expandable polystyrene is a lightweight cellular material consisting of fine spherical shaped particles which are comprised of 98% air and 2% polystyrene. It is a rigid cellular plastic containing an expansion agent called pentane.
EPS Bead has low thermal conductivity and low moisture absorption. It is lightweight, safe and easy to use.
EPS BEAD
The Energy Company Obligation
The Energy Company Obligation (ECO) is a government energy efficiency scheme in Great Britain which aims to help reduce carbon emissions and tackle fuel poverty.
The scheme began in April 2013, and over time it has been amended. The latest policy, ECO3, commenced on 3 December 2018, and applies to measures completed from 1 October 2018.
Under ECO3, obligated suppliers must provide funding for measures which improve the ability of low income, fuel poor and vulnerable households to heat their homes.
This includes grant funding for actions that result in heating savings, such as cavity wall insulation, solid wall insulation and loft insulation.

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