What It Is
Cavity wall insulation involves injecting insulation material into the gap between the inner and outer leaves of a property's external walls. This significantly reduces heat transfer through the walls, improving thermal performance and reducing energy consumption.
Why It Matters
Around 35% of heat loss in an uninsulated home occurs through the walls. Filling cavity walls is one of the highest-impact energy efficiency measures available.
- One of the highest-impact retrofit measures
- Fast installation with minimal disruption
- Immediate thermal improvement
- Significant reduction in energy bills
Who It's For
What Good Delivery Looks Like
Thorough pre-installation survey including borescope inspection
Correct drill pattern and injection technique
Proper sealing of all drill holes
Full evidence packs documenting the installation
Interested in Cavity Wall Insulation?
Discuss your cavity wall insulation project. Get in touch to discuss your requirements or request a survey.
Exploring the North East Warm Homes Loan?
Lendology lists this type of work among the measures it may consider, subject to its own eligibility checks. WHNZ can survey and quote the work; you apply to Lendology independently. Registration opened 8 October 2026; full applications open 22 October 2026.
Other Services
Delivering a programme rather than a single property? See managed retrofit delivery. To check coverage, see the areas we serve, or read more about how Warm Homes Net Zero Ltd works.