Outbuilding approval rate in Hounslow

Hounslow approved 80.9% of outbuilding applications, based on 4,207 decisions analysed.

Last updated: August 2026

80.9%

outbuilding approval rate

4,207

Outbuilding decisions

3,404

Approved

803

Refused

87.9%

Hounslow overall

Outbuilding applications are refused more often than the Hounslow average (87.9%), suggesting the council scrutinises these projects more closely.

How outbuilding compares in Hounslow

Outbuilding (4,207 decided)

80.9%

Hounslow all applications (73,101 decided)

87.9%

Planning a outbuilding in Hounslow?

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Other project types in Hounslow

Rear Extension (26,811 decided)

85.0%

Loft Conversion (12,130 decided)

89.7%

Garage / Parking (8,772 decided)

88.9%

Side Extension (7,853 decided)

88.1%

New Build (4,808 decided)

90.3%

Hip-to-Gable Conversion (3,282 decided)

85.5%

Change of Use (Residential) (3,110 decided)

82.7%

Extension (General) (3,055 decided)

92.9%

Conservatory (1,940 decided)

94.7%

Wraparound Extension (1,518 decided)

88.9%

Basement (1,496 decided)

90.0%

Dormer (1,432 decided)

89.9%

Flat Conversion (1,420 decided)

73.0%

Front Extension (1,046 decided)

82.9%

HMO (353 decided)

48.7%

Annex (108 decided)

69.4%

← All Hounslow planning statistics

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