Annex approval rate in Blackburn with Darwen

Blackburn with Darwen approved 89.8% of annex applications, based on 88 decisions analysed.

Last updated: June 2026

89.8%

annex approval rate

Annex decisions

Approved

Refused

89.1%

Blackburn with Darwen overall

Annex applications are approved at roughly the same rate as the Blackburn with Darwen average (89.1%).

How annex compares in Blackburn with Darwen

Annex (88 decided)

89.8%

Blackburn with Darwen all applications (12,714 decided)

89.1%

Planning a annex in Blackburn with Darwen?

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Other project types in Blackburn with Darwen

Rear Extension (2,200 decided)

90.3%

Extension (General) (1,931 decided)

87.9%

Garage / Parking (1,414 decided)

89.0%

Change of Use (Residential) (1,090 decided)

78.5%

Side Extension (1,073 decided)

88.4%

Dormer (571 decided)

82.3%

New Build (458 decided)

84.3%

Conservatory (314 decided)

92.7%

Outbuilding (287 decided)

88.9%

Wraparound Extension (221 decided)

86.0%

Front Extension (159 decided)

88.1%

Basement (103 decided)

87.4%

Flat Conversion (102 decided)

71.6%

Hip-to-Gable Conversion (72 decided)

91.7%

Loft Conversion (64 decided)

84.4%

HMO (29 decided)

55.2%

← All Blackburn with Darwen planning statistics

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