Rear extensions are the bread and butter of UK planning — and one of the most common reasons homeowners face a refusal. Here's what 4,812 real decisions tell us about rear extension outcomes in Harrow.
See your ward's approval rate and nearby planning decisions — free and instant.
Rear extensions sit in the middle of the pack nationally. They're common enough that councils have clear precedent — but that cuts both ways. If your neighbours have been refused, that precedent works against you too.
| # | Ward | Decisions | Approved | Rate |
|---|---|---|---|---|
| 1 | Stanmore | 6 | 6 | 100.0% |
| 2 | Harrow on the Hill | 5 | 5 | 100.0% |
| 3 | Edgware | 5 | 4 | 80.0% |
| 4 | Pinner South | 7 | 5 | 71.4% |
| 5 | Belmont | 5 | 3 | 60.0% |
A rear extension has a 100.0% approval rate in Stanmore but just 60.0% in Belmont.
Check your postcode to see what actually happens near your address.
Not all applications are treated equally. Here's how rear extensions stack up against other common projects in Harrow.
| Type | Decisions | Rate |
|---|---|---|
| Flat Conversion | 829 | 92.2% |
| Basement | 307 | 85.0% |
| Change of Use (Residential) | 642 | 83.8% |
| Wraparound Extension | 223 | 82.5% |
| Garage / Parking | 3,138 | 81.8% |
| Extension (General) | 684 | 81.4% |
| Conservatory | 317 | 81.4% |
| Loft Conversion | 88 | 80.7% |
| Outbuilding | 974 | 79.1% |
| New Build | 139 | 79.1% |
| Rear Extension | 4,812 | 78.2% |
| Dormer | 2,458 | 77.3% |
| Front Extension | 1,029 | 77.1% |
| HMO | 155 | 76.8% |
| Hip-to-Gable Conversion | 20 | 75.0% |
| Side Extension | 2,430 | 74.7% |
| Annex | 54 | 42.6% |
1,050 rear extension applications in Harrow have been refused since 2020. Many of those homeowners had already paid for drawings and application fees. A £79 report shows you what gets approved — and what gets refused — near your property.
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