Heat will always flow from a warm area to a cold one. In winter, the colder it is outside, the faster heat from your home will escape into the surrounding air. In general, houses built from the 1990s onwards have wall insulation to keep the heat in, but if your house is older than that it may not have any wall insulation. If this is the case then you may be losing a lot of heat from your home, as heat can escape more quickly through uninsulated walls. Most types of wall can be insulated in one way or another. If you have a typical house with cavity walls, you could save up to £155 per year (based on a semi-detached house) in heating bills just from insulating the walls. The first thing you need to find out is what sort of walls you have.
So what is Cavity Wall Insulation?
Most homes built after 1935 will be constructed with a masonry cavity wall. This is where there is a gap between your internal and external wall which can be filled by drilling a series of holes and pumping in either mineral wool or a polystyrene bead. The work only takes around half a day to complete. Homes built after 1995 should already have adequate levels of insulation in the cavity.
How to check if your house already has cavity wall insulation
If your house was built after the mid-1930s, chances are it has cavity walls. To check, have a look at the outside of your house:
- Measure your window sills, if they exceed 10 inches, you probably have cavities
- You can also tell by looking at the brick pattern. If your home has cavity walls, the bricks will all look the same size, whereas if your walls are solid and therefore unsuitable for cavity wall insulation, every other brick will probably be placed end-on.
Once you’ve established that your house does in fact have cavity walls, the next step is to check whether or not they’re insulated.
Cavity wall insulation works by filling the gap between your internal and external walls with an insulating material, which helps to keep heat in and reduce your energy bills. There are two main types of cavity wall insulation –
If there is a drilling pattern within the mortar joints on the external walls of your home, this usually is a good indicator that your home has been insulated. The drilling pattern will vary depending on the type of insulation material used to insulate your walls.
For example, if your home has been insulated with mineral wool, typically the drilling pattern on the front of your house will look like the below:
The drilling pattern is different if your home has been insulated with polystyrene bead insulation, typically like the below:
If you’re still not sure, you can contact Dyson Energy Services, a professional insulation company or surveyor to come and take a look for you. They have special tools such as a borescope that can allow them to drill a small hole in the mortar and view the cavity.
How do I get free cavity wall insulation?
If you or a member of your household is on a qualifying benefit, you may qualify for free cavity wall insulation through the government Energy Company Obligation (ECO) scheme.
Check out our funding page for further details, on the insulation grants available.
New government driven standards
New government driven standards, that came into effect from the 1st of July, mean that householders who sign up to funded energy efficiency measures through the Energy Company Obligation (ECO) scheme, will benefit from a new requirement to install additional ventilation in their homes, where required.
How much money could I save?
According to figures from the Energy Saving Trust website, cavity wall insulation could save on average £155 per year (based on a semi-detached house).
“We have to do our bit for future generations”
Neil and Karen, a couple from Somerset, recently had cavity wall and loft insulation installed, which was funded through the Energy Company Obligation scheme and installed by Dyson Energy Services. They were keen to tell their story in the hope that it encouraged others to benefit from energy-saving insulation too.
Read their story.
Read the frequently asked questions from our customers below.
