Skip to main content
Housey Data Report

Where a house extension still pays for itself (2026)

By Housey · Data: UK HPI average price, 01/04/2026

In Kensington and Chelsea, £50,000 of builder's dust turns into 5.4× its cost in added value; in Hartlepool, the very same extension adds less than it costs to build. A typical £50,000 rear extension clearly pays for itself in 175 of 295 English areas — is yours one of them?

295
Areas ranked
175
Where it pays off

59% of areas

5.4×
Best return

Kensington and Chelsea

0.5×
Worst return

Hartlepool

Payback ×
< 0.9
0.9 to 1.1
1.1 to 1.3
1.3 to 1.5
1.5 to 1.9
≥ 1.9
Every English authority shaded by Payback ×. Unlock the report to search your area, read the exact figures, and download the data.
#Local authorityPayback ×Net value addedLocal £/m²
1Kensington and Chelsea5.4£220,800£13,540
2City of Westminster3.5£123,336£8,667
3Camden3.4£119,048£8,452
+ 289 more authorities — unlock the full ranking below
293Blackpool0.6£-21,334£1,433
294Burnley0.6£-22,435£1,378
295Hartlepool0.5£-22,526£1,374

Methodology & sources

Whether a typical 20m² rear extension (£50,000 build) adds more value than it costs, using local £/m² derived from UK HPI average prices. Payback × = value added ÷ build cost.

Unlock the full ranking

Enter your email to see every authority in Where a house extension still pays for itself (2026), search for your area, and download the full dataset as CSV. We'll also email you when we publish a new report.

By continuing you agree to receive Housey data reports and related emails. Unsubscribe any time. No spam.