50% of width of original house for extension rule

18 Oct 2013
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United Kingdom
Can i please confirm:

The rule regarding no more than 50% of the width of the original house, when doing a house extension, relates only to side extensions and not rear extensions correct? So if you have a square house, you can go across the width of the house 4m deep on a detached?

Is the answer any different when you have an L shaped house, is the recessed or void area considered a side or rear extension when you want to infill that area?
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If the back of your house is in one plane, yo can go full-width across under p.d.

If it is L-shaped, and the projecting-part is less than 1/2 the width of the house, you are caught out because the side wall of the outrigger will be classed as 'a wall forming part of the side elevation of the ...... house'
(para. A1(h)

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