External wall insulation
Plain-English research on external wall insulation (EWI) in the UK: what it costs, grants available, energy savings by house type, and whether it makes sense for solid-walled homes.
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Cornerstone · 8 min read
Is external wall insulation worth it?
The 2026 cost and payback answer for UK homes. Installation cost, ECO4 grants, energy savings by house type, and what external wall insulation won't fix.
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