Cavity wall insulation is a common solution for heat loss in buildings throughout much of the world.
Find products Other applications DownloadsCavity wall insulation is installed in the space between in the inner and outer leaves of both external and party walls in many building types, both in new build and renovated properties. The latter includes numerous UK homes dating back to the 1920s.
Without adequate insulation, properties will lose more heat – resulting in greater energy use to warm them effectively, and higher bills.
Discover more about the benefits, products and installation methods of ROCKWOOL cavity insulation today.
Fitting insulation for cavity walls is among the quickest and most cost-effective ways to improve energy efficiency.
An uninsulated cavity will result in increased heat loss during a cold period. In fact, around a third of the heat lost escapes through uninsulated cavity walls1.
Cavity wall insulation acts like a blanket that stops heat escaping. It retains the heat and releases it back into the internal space. The insulation also keeps the home cool in summer, so the property maintains a comfortable indoor temperature and doesn’t overheat.
Key benefits include:
The exact cost of installing cavity insulation and the energy savings it can bring will depend on property size and type.
Stone wool insulation can be installed as partial or full fill, with the thickness of insulation required being determined by building regulations and the specified thermal performance.
Generally, you should recoup the installation cost within five years, with research suggesting it can save you up to £285 per year on energy bills in the UK.2
|
Property type |
Energy bill savings (per year) |
CO² savings (kg/CO² per year) |
|
Detached house |
£285 |
1185 |
|
Semi-detached house |
£170 |
695 |
|
Mid terrace |
£105 |
430 |
|
Bungalow |
£115 |
470 |
|
Flat |
£80 |
3253 |
Use the ROCKWOOL U-value calculator to determine the thermal performance of the building’s walls.
We offer three types of wall cavity insulation. Each has its own benefits:4
ROCKWOOL cavity wall insulation also uses the power of stone to create resilient, long-lasting and effective solutions.
Benefits include:
With cavity wall slab insulation, the amount required matches the m² area of the property’s wall (minus openings such as doors and windows).
Working out the amount of loose fill cavity wall insulation is more complex – this is blown into the cavity through holes in the wall by specialised installers. Contact a registered installer for more information, they will check your property for suitability and recommend the best type of insulation to use.
Insulation for masonry cavity walls. Cavity datasheet includes applications, performance, installation guidance and product specification text.
Robust, long-lasting protection for masonry cavity walls. HP Partial Fill Cavity Slab datasheet includes applications, performance, design guidance, installation and NBS clauses.
Minimises thermal bridging at door and window reveals in cavity wall constructions. ROCKCLOSE datasheet includes information on applications, performance, installation guidance and NBS clauses.
Check the Energy Savings Trust website to see whether there are any financial support schemes available for cavity wall insulation.
