PPS 7 Addendum Residential Extensions and Alterations·Page 23·Footnote 2
Definition of Dwellinghouse for Permitted Development
For permitted development purposes, a dwellinghouse excludes buildings containing one or more flats, flats within such buildings, and any house or flat in multiple occupation.
For the purposes of permitted development a dwelling house does not include a building containing one or more flats, or a flat contained within such as building. It also excludes any house or flat in multiple occupation.
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