Roof insulation
Roof insulation (insulating the underside of the roof rather than the loft floor) makes most sense when converting a loft into living space or heating a room-in-roof. Costs £2,500 to £7,000 and saves £200 to £350 per year.
Cornerstone guide
Is roof insulation worth it?
The honest 2026 answer for UK homeowners. Costs by roof type, savings on heating bills, grants available, and when roof insulation makes sense (pitched roofs, flat roofs, and when to choose loft insulation instead).
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