Loft Conversions Wimbledon
Rear loft extensions are considered permitted development, providing they conform to the following:

The additional roof volume created should not exceed 40m3 for attached houses and 50m3 for detached & semi-detached houses (the original house).
The additional roof construction must NOT exceed the existing height of the roof or the original house.
Any window on the side elevation must NOT be opening below 1.7m from the finished floor level and have obscured glazing.
The additional roof construction must be set back at least 200mm from the face of the external wall, a distance measured along the roof plane.
Balconies, Verandas or raised platforms are NOT permitted


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