278Assumptions as to planning permission in determining value of interests in land
(1)In any case where the value or depreciation in value of an interest in land falls to be determined on the assumption that planning permission would be granted for development of any class specified in Schedule 8 to this Act, it shall be further assumed, as regards development of any class specified in paragraph 1 or 3 of that Schedule, that such permission would; be granted subject to the condition set out in Schedule 18 to this Act.
(2)In the application of the said Schedule 8 for the purposes of any determination to which subsection (1) of this section applies—
(a)paragraph 3 of that Schedule shall be construed as not extending to works involving any increase in the cubic content of a building erected after the appointed day (including any building resulting from the carrying out of such works as are described in paragraph 1 of that Schedule); and
(b)paragraph 7 of that Schedule shall not apply to any such building.
(3)For the purposes of subsections (1) and (2) of this section, so far as applicable to any determination of existing use value as defined in section 187(5) of this Act, references to Schedule 8 to this Act, and to paragraphs 1, 3 and 7 of that Schedule, shall be construed as references to Schedule 3 to the Act of 1947 and to the corresponding paragraphs of that Schedule; and that Schedule shall have effect as if it contained a paragraph corresponding to paragraph 13 of Schedule 8 to this Act.
(4)Except as provided in section 168(4) of this Act, nothing in the preceding provisions of this section or in paragraph 13 of Schedule 8 affects the meaning of "new development" in this Act or any determination to be made for the purpose of Part VIX of this Act.
(5)For the avoidance of doubt it is hereby declared that where, under any provision of this Act, the value of an interest in land is required to be assessed on the assumption that planning permission would be granted for development of any class specified in Schedule 8 to this Act, that assumption is to be made on the footing that any such development must comply with the provisions of any enactment, other than this Act, which would be applicable to it.