Loft conversion and dormer planning approval rate in Hillingdon
74% of 585 decided loft conversion and dormer applications in Hillingdon 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.
74%
Approval rate, all years, from 585 decided
585
decided loft conversion and dormer applications in Hillingdon: 430 approved, 155 refused
74%
Recent rate, decided since 2022, from 319 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 Withdrawn applications are excluded.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 2003 to 2026. 0 of 585 decided records have no year recorded. Coverage may have gaps within the date range.
319 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 Hillingdon, or read about permitted development in Hillingdon. An approval rate does not decide which route your property qualifies for.
Example loft conversion and dormer decisions in Hillingdon
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 Hillingdon's planning register using the references below. Descriptions may be shortened; read the complete proposal and decision notice.
| Reference | Year | Decision | Application |
|---|---|---|---|
| 16043/APP/2026/229 | 2026 | Approved | Conversion of roof space to habitable use to include a rear dormer and extension of roof from hip to gable end. Erection of outbuilding to rear garden (Appli... 16 MILTON CLOSE |
| 19583/APP/2025/2779 | 2026 | Approved | Conversion of roof space to habitable use to include rear dormer (Application for a Certificate of Lawful Development for a Proposed Development). 68 ATTLEE ROAD |
| 21324/APP/2025/2952 | 2026 | Approved | Erection of a roof extension to enlarge the existing dormer. 13 BROADWAY PARADE |
| 11253/APP/2025/1417 | 2025 | Refused | Construction of one additional storey (Application for Prior Approval under Schedule 2, Part 1, Class AA of the Town and Country Planning (General Permitted... 43A WOODSTOCK GARDENS |
| 11329/APP/2025/202 | 2025 | Refused | Conversion of roof space to habitable use to include a rear dormer, conversion of roof from hip to gable end and removal of chimney stack (Application for a... 54 BRIDGWATER ROAD |
| 16721/APP/2024/3357 | 2025 | Refused | Conversion of integral garage to habitable accommodation, erection of a part single, part double storey extension to the side and rear and installation of a... 12 COTTAGE CLOSE |
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 Hillingdon
- Single-storey rear extension 83%, 7,240 decided
- Two-storey rear extension 66%, 2,756 decided
- Wraparound extension 79%, 844 decided
- Side extension 71%, 1,686 decided
- Rooflight 89%, 2,768 decided
- Outbuilding and garden room 81%, 1,230 decided
- Porch 75%, 374 decided
- Garage conversion 89%, 425 decided
- Basement 86%, 432 decided
- Window and door 86%, 496 decided