80Planning permission for erection of two or more buildings where no office development permit required
(1)The provisions of this section shall have effect with respect to any planning permission for development involving the erection of two or more buildings on land which is within a controlled area when the planning permission is granted and was also within such an area when the application for planning permission was made, except in a case where all the buildings are exempt from this section.
(2)Any one of the said buildings shall be exempt from this section if—
(a)it is wholly residential; or
(b)the planning permission is subject to conditions by virtue of section 70(5) or (6) of this Act and those conditions either restrict the office floor space which the building may contain or preclude it from containing any office floor space.
(3)If the aggregate floor space of the buildings proposed to be erected (leaving out of account any which are exempt from this section) is twice, or more than twice, the prescribed exemption limit, and either the erection of the buildings is not development to which these provisions apply or it is such development but no office development permit is required for it, the planning permission shall be granted subject to the condition specified in subsection (4) of this section (in addition to any other conditions imposed by the authority granting the permission).
(4)The said condition is that the use of each one of the buildings (excluding any which are exempt from this section) shall be restricted so that (whether in consequence of "a change of use or otherwise) it does not at any time contain office premises having an aggregate floor space which exceeds the limit for that building specified in the condition, which limit shall (subject to subsection (5) of this section) be a floor space bearing such proportion to the building's total floor space as the prescribed exemption limit bears to the aggregate floor space of all the buildings (excluding any which are exempt from this section) for whose erection the planning permission is granted.
(5)The authority granting the planning permission may in doing so specify in the said condition, as it applies to any building, a limit differing from the one provided by subsection (4) of this section, but not so that the total of the limits for all the buildings to which the condition applies exceeds the prescribed exemption limit.
(6)If after the grant of the planning permission a further application for planning permission is made in respect of all or any of the buildings to which the condition specified in subsection (4) of this section applies, and the further application involves a departure from the terms of the said condition as applying to any building, the application shall be subject to section 74(1) of this Act notwithstanding anything in these provisions exempting development from the requirements of that section in particular cases.