Policy information sourced from Hammersmith & Fulham Planning Guidance
HS4 Rear extensions
The council will have regard to the existing established rear building lines of adjoining properties in determining applications for rear extensions which project beyond the rear building line of the property as originally built. However, planning permission will not normally be granted for any extension if:
- The proposed extension is more than 3.5 metres in length or, where the original property has already been extended, if the combined length of the existing and the proposed extensions would project more than 3.5 metres beyond the rear building line of the back addition as it was originally built; or
- The proposed extension would extend to within 4 metres of the rear boundary of the application property; or
- The proposed extension would cover more than 50% of the open area at the rear of the property as originally built or, where the original property has already been extended, if the cumulative area of the existing and proposed extensions would cover more than 50% of the open area at the rear of the property as originally built.
For more information please see the Hammersmith & Fulham Planning Guidance