Rear extensions in Glamorgan
3,662 applications since 2016. 3,292 approved and 162 refused. Refused: about 1 in 21 here, about 1 in 7 across the councils we cover.
Last updated 8 November 2026.
Without planning permission
- Up to 3 m deep on a terrace or semi, 4 m on a detached house
- Up to 6 m or 8 m through the neighbour-consultation route, not on protected land
- No higher than 4 m, and eaves no higher than 3 m within 2 m of a boundary
- Together with other buildings, no more than half the garden and grounds
- Materials similar in appearance to the house
England, houses only. Flats, listed buildings, conservation areas and Article 4 directions change this. The full rules.
Year by year
| Year | Applications | Approved | Refused |
|---|---|---|---|
| 2026 | 194 | 117 | 14 |
| 2025 | 290 | 252 | 17 |
| 2024 | 263 | 231 | 17 |
| 2023 | 321 | 280 | 22 |
| 2022 | 402 | 367 | 21 |
| 2021 | 463 | 433 | 18 |
| 2020 | 374 | 341 | 17 |
| 2019 | 357 | 333 | 9 |
| 2018 | 370 | 350 | 8 |
| 2017 | 307 | 294 | 6 |
| 2016 | 321 | 294 | 13 |
Architects and agents, last 5 years
| Firm | Approved | Decided |
|---|---|---|
| Christian Le Guilcher, Le Guilcher Architecture | 77 | 79 |
| Martin Coles, Dennis Hellyar Architects | 19 | 19 |
| Laurence Clarke, Plan-It Design (Wales) Ltd | 13 | 14 |
| Dennis Hellyar, Dennis Hellyar Architects | 12 | 12 |
| Meridian Building Design | 7 | 7 |
| Creative Design Solutions | 6 | 7 |
| Jesus Ramos, Dennis Hellyar Architects | 5 | 5 |