Outbuilding approval rate in Hounslow

Hounslow approved 80.6% of outbuilding applications, based on 4,193 decisions analysed.

Last updated: June 2026

80.6%

outbuilding approval rate

4,193

Outbuilding decisions

3,380

Approved

813

Refused

87.6%

Hounslow overall

Outbuilding applications are refused more often than the Hounslow average (87.6%), suggesting the council scrutinises these projects more closely.

How outbuilding compares in Hounslow

Outbuilding (4,193 decided)

80.6%

Hounslow all applications (72,995 decided)

87.6%

Planning a outbuilding in Hounslow?

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Other project types in Hounslow

Rear Extension (26,741 decided)

84.9%

Loft Conversion (12,095 decided)

89.7%

Garage / Parking (8,803 decided)

88.4%

Side Extension (7,834 decided)

88.0%

New Build (4,819 decided)

89.9%

Hip-to-Gable Conversion (3,271 decided)

85.3%

Change of Use (Residential) (3,114 decided)

82.5%

Extension (General) (3,050 decided)

92.8%

Conservatory (1,942 decided)

94.6%

Wraparound Extension (1,509 decided)

89.0%

Basement (1,499 decided)

89.1%

Flat Conversion (1,423 decided)

72.9%

Dormer (1,416 decided)

90.0%

Front Extension (1,047 decided)

82.8%

HMO (358 decided)

48.3%

Annex (110 decided)

68.2%

← All Hounslow planning statistics

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