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Rear Extension Approval Rates in Arun

Rear extensions are the bread and butter of UK planning — and one of the most common reasons homeowners face a refusal. Here's what 353 real decisions tell us about rear extension outcomes in Arun.

353 real decisions·January 2020 to July 2026·Updated August 2026
97.5%
Approval Rate
353
Decisions
344
Approved
9
Refused
97.5% approved. But 9 refused since 2020. Each refusal cost the homeowner time and money on drawings and application fees. Understanding your local data before you apply is the difference between confidence and a costly gamble.

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Why rear extension approval rates matter

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.

These are council averages. Your property is specific.

Two houses on the same street can get different outcomes.
Check your postcode to see what actually happens near your address.

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How rear extensions compare to other project types

Not all applications are treated equally. Here's how rear extensions stack up against other common projects in Arun.

TypeDecisionsRate
Conservatory115
99.1%
Rear Extension353
97.5%
Front Extension70
97.1%
Side Extension162
96.9%
Hip-to-Gable Conversion27
96.3%
Loft Conversion77
96.1%
Wraparound Extension20
95.0%
Dormer157
94.9%
Extension (General)115
94.8%
Outbuilding89
94.4%
Change of Use (Residential)28
92.9%
Garage / Parking297
91.2%
Annex23
82.6%
New Build36
80.6%
See how this applies to your postcode →

What the data tells us

1
97.5% of rear extension applications in Arun get approved. That means 9 homeowners since 2020 have been refused. Not terrible odds, but not a foregone conclusion.
3
Council averages are starting points, not guarantees. The decisions that matter most are the comparable ones near your specific property — because planning officers look at precedent, character and the immediate context of your street.

Before you spend £5,000+ on architects and drawings

9 rear extension applications in Arun have been refused since 2020. Many of those homeowners had already paid for drawings and application fees. A free, property-specific report shows you what gets approved — and what gets refused — near your property.

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Free · Property report emailed in minutes · Based on 3,780,000+ real decisions

More Arun planning data

Methodology: Based on 353 planning decisions classified as rear extensions in Arun, January 2020 to July 2026. Classification uses keyword matching against proposal descriptions (matching generate_site_data.py rules). A single application may appear in multiple categories. Approval rate = approved / (approved + refused). Pending, withdrawn and invalid applications excluded. Data from Arun Council's public planning portal. Full methodology →
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