PPS 7 Addendum Residential Extensions and Alterations·Page 18·A34
Daylighting assessment for rooms
Planning permission will likely be refused if an extension would reduce light entering windows of habitable rooms (excluding halls, landings, bathrooms, and utility rooms) to an unreasonable degree.
In terms of daylighting, the effect on all rooms, apart from halls, landings, bathrooms and utility rooms will be considered. Where an extension would be likely to reduce the amount of light entering the window of a room, other than those indicated above, to an unreasonable degree, planning permission is likely to be refused.
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