Outbuilding and garden room planning approval rate in Hertsmere
78% of 274 decided outbuilding and garden room applications in Hertsmere were approved.
Checked against 20.6 million UK planning applications on file across 420 planning authorities. Approval rates from 2,343,419 decisions we classified across 181 councils in England.
A similar project nearby can help you understand the council's decisions. Its outcome does not establish what will be acceptable at your address.
78%
Approval rate, all years, from 274 decided
274
decided outbuilding and garden room applications in Hertsmere: 214 approved, 60 refused
79%
Recent rate, decided since 2022, from 128 decided
How to read these rates
These are historical outcomes for the applications in our archive, not the chance of approval for your property. Compare the same project type and read the decided count alongside each percentage.
About the planning data
Rate = approved divided by approved plus refused, using the decisions in our classified archive. Rates are withheld as unknown where fewer than 8 records of that project type were decided. Withdrawn applications are excluded. The eight-record threshold is a display rule, not a guarantee that a sample is statistically reliable.
Recent means records dated 2022 or later. Records without a year are excluded from the recent rate but remain in the all-years figure. Historical coverage varies by council, and duplicate application references may remain in the archive.
Approval rates from 2,343,419 decisions we classified across 181 councils in England. The wider 20.6 million application catalogue is accessible through PlanIT; it is not the dataset used to calculate these percentages.
Read the full methodology and coverage notes.
Project types and outcomes are classified from council records. Check the original application and decision notice before relying on an individual example. A page rebuild does not mean every council record has just been refreshed.
Coverage for this project type
Dated records in this archive span 2015 to 2026. 0 of 274 decided records have no year recorded. Coverage may have gaps within the date range.
128 decided records are dated 2022 or later. This is an archive count, not a measure of all current council activity.
These project categories can include different application routes and proposals combining several kinds of work. Read the proposal and decision type before comparing it with your project.
Check planning requirements in Hertsmere, or read about permitted development in Hertsmere. An approval rate does not decide which route your property qualifies for.
Example outbuilding and garden room decisions in Hertsmere
These examples deliberately include approved and refused applications where available. They are not a representative sample or a list of the latest decisions. Look up each reference on the council's planning search to read the plans and decision notice.
Search Hertsmere's planning register using the references below. Descriptions may be shortened; read the complete proposal and decision notice.
| Reference | Year | Decision | Application |
|---|---|---|---|
| 25/1331/CLE | 2026 | Approved | Erection of new outbuilding to rear garden for ancillary use. Certificate of Lawful Development (Existing). 27 Park View Potters Bar Hertfordshire EN6 5PY |
| 25/1611/CLP | 2026 | Approved | Erection of outbuilding in rear garden. Certificate of lawful development (Proposed). 244 Gateshead Road Borehamwood Hertfordshire WD6 5LJ |
| 25/1721/HSE | 2026 | Approved | Erection of an outbuilding and heat pump in rear garden. (Retrospective application) 35 Craigweil Avenue Radlett Hertfordshire WD7 7ET |
| 24/1554/VOC | 2025 | Refused | Application for variation of condition 3 (outbuilding) to allow for removal of condition following grant of planning permission 24/1126/HSE. 59 Cowley Hill Borehamwood Hertfordshire WD6 5LQ |
| 24/1659/VOC | 2025 | Refused | Application for variation of condition 2 (plans) to allow for relocation of rear garden outbuilding, alteration to porch roof and to alignment of front dorme... 32 Links Drive Radlett Hertfordshire WD7 8BE |
| 25/0295/CLP | 2025 | Refused | Erection of outbuilding in rear garden. Certificate of lawful development (Proposed). 7 Heath Road Potters Bar Hertfordshire EN6 1LQ |
About the planning data
Checked against 20.6 million UK planning applications on file across 420 planning authorities. Approval rates from 2,343,419 decisions we classified across 181 councils in England.
Other project types in Hertsmere
- Single-storey rear extension 81%, 1,787 decided
- Two-storey rear extension 85%, 972 decided
- Wraparound extension 92%, 436 decided
- Side extension 84%, 702 decided
- Loft conversion and dormer 79%, 281 decided
- Rooflight 90%, 918 decided
- Porch 90%, 195 decided
- Garage conversion 96%, 294 decided
- Basement 84%, 136 decided
- Window and door 90%, 223 decided