The Town and Country Planning (General Permitted Development) Order 1995

[F1Development not permittedE+W

A.1.  Development is not permitted by Class A if—

(a)the development would affect a listed building or its setting;

(b)the height of the building would exceed 12 metres;

(c)where the development is within three kilometres of an aerodrome, the height of the building would exceed three metres;

(d)the area of ground which would be covered by the building would exceed 465 square metres;

(e)where development permitted by Class A is carried out more than once on land in the occupation of a particular person, the aggregate of the area of ground covered by any such development would exceed 465 square metres;

(f)where the development consists of the extension of a building, the area of ground covered by the building as extended would exceed the area of ground covered by the existing building by more than 50 per cent.]