Insulation is the unglamorous upgrade that pays for itself fastest. Loft insulation often pays back in under 2 years. Select your property, tick what you want to add, and we'll show the savings, costs, and whether ECO4 might cover it free.
If you're on benefits or have a household income under £31,000 and an EPC of D or below, ECO4 can cover loft insulation, cavity wall, and even solid wall insulation at no cost. The scheme closes 31 December 2026 — apply now.
The Warm Homes Local Grant (England) covers similar measures for low-income households through local councils.
Use our grants eligibility checker to see what you qualify for.
1. Loft insulation — cheapest, fastest payback, easiest to install. DIY possible for simple loft spaces.
2. Draught-proofing — very cheap, often overlooked. Chimney balloons, door strips, window seals.
3. Cavity wall — if your home has unfilled cavities (most 1930s–1990s builds), this is the biggest single saving.
4. Underfloor — good ROI on suspended timber floors. Not practical for solid concrete floors.
5. Solid wall — biggest saving per measure but highest cost. Internal is cheaper but loses room space; external changes the building's appearance (may need planning).