A.1 Development not permitted
Development is not permitted by Class A(e) if—
(a)it would consist of or include the extension or alteration of a building so that—
(i)its design or external appearance would be materially affected;
(ii)the height of the original building would be exceeded, or the cubic content of the original building would be exceeded, by more than 25%; or
(iii)the floor space of the original building would be exceeded by more than 1,000 square metres;
or
(b)it would consist of the installation or erection of any plant or machinery exceeding 15 metres in height or the height of anything it replaces, whichever is the greater.