Side Extension approval rate in Hertsmere
Hertsmere approved 87.2% of side extension applications, based on 360 decisions analysed.
Last updated: August 2026
87.2%
side extension approval rate
360
Side Extension decisions
314
Approved
46
Refused
87.8%
Hertsmere overall
Side Extension applications are approved at roughly the same rate as the Hertsmere average (87.8%).
How side extension compares in Hertsmere
Side Extension
87.2%
Hertsmere all applications
87.8%
Planning a side extension in Hertsmere?
87.2% 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 side extension approval rate
✓ Nearest comparable side extension decisions
✓ Refusal triggers specific to your area
✓ PDF report for your architect
Free planning check for Hertsmere →
✓ Nearest comparable side extension decisions
✓ Refusal triggers specific to your area
✓ PDF report for your architect
Other project types in Hertsmere
86.6%
91.4%
91.2%
87.9%
95.0%
89.1%
92.9%
94.8%
82.5%
83.2%
89.3%
93.8%
100.0%
100.0%