Data-backed planning intelligence · 3,200,000+ decisions analysed across England, Scotland, Wales and Northern Ireland

Rear Extension approval rate in Cardiff

Cardiff approved 67.9% of rear extension applications, based on 364 decisions analysed.

Last updated: June 2026

67.9%
rear extension approval rate
364
Rear Extension decisions
247
Approved
117
Refused
81.7%
Cardiff overall

Rear Extension applications are refused more often than the Cardiff average (81.7%), suggesting the council scrutinises these projects more closely.

How rear extension compares in Cardiff

Rear Extension (364 decided)
67.9%
Cardiff all applications (4,803 decided)
81.7%

Planning a rear extension in Cardiff?

67.9% get approved, but the odds vary by street. Your Full Planning Analysis shows exactly what gets approved and refused near your property.

✓ Your ward's rear extension approval rate
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Other project types in Cardiff

Garage / Parking (293 decided)
66.9%
Extension (General) (293 decided)
66.6%
Dormer (216 decided)
85.6%
Loft Conversion (205 decided)
70.2%
Conservatory (176 decided)
49.4%
Side Extension (154 decided)
65.6%
59.6%
Outbuilding (81 decided)
77.8%
84.1%
HMO (29 decided)
82.8%
Annex (28 decided)
78.6%
Flat Conversion (26 decided)
88.5%
Front Extension (24 decided)
83.3%
New Build (21 decided)
71.4%
77.8%
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