8. After class 7 (the erection, construction, maintenance, improvement or alteration of a gate, fence, wall or other means of enclosures) insert—
“Class 7A
(1) Any alteration or replacement of an existing window(1).
(2) Development is not permitted by this class within a World Heritage Site.
(3) Paragraph (4) applies to development to alter or replace a window in a conservation area where—
(a)the window is part of—
(i)the principal elevation, or
(ii)a side elevation where that elevation fronts a road, and
(b)the window as altered or replaced would not be the same, or substantially the same, as the window to be altered or replaced in the following respects—
(i)the manner in which the window is opened and closed,
(ii)the number, orientation and colour of the panes comprised in the window,
(iii)the dimensions and colour of the frame of the window or any astragal bars comprised in the window.
(4) Development to which this paragraph applies is permitted by this class subject to the following conditions—
(a)the developer must, before beginning the development, apply to the planning authority for a determination as to whether the prior approval of the authority will be required in respect of the design and external appearance of the proposed alteration to or replacement window,
(b)the application is to be accompanied by a written description of the proposed development, the materials to be used and a plan indicating the site together with any fee required to be paid,
(c)the development is not to be commenced before the occurrence of one of the following—
(i)the receipt by the applicant from the planning authority of a written notice of their determination that such prior approval is not required,
(ii)where the planning authority gives the applicant notice within 28 days following the date of receiving the application of their determination that such prior approval is required, the giving of such approval,
(iii)the expiry of 28 days following the date on which the application was received by the planning authority without the planning authority making any determination as to whether such approval is required or notifying the applicant of their determination,
(d)the development must, except to the extent that the planning authority otherwise agree in writing, be carried out—
(i)where prior approval is required, in accordance with the details approved, or
(ii)where prior approval is not required, in accordance with the details submitted with the application, and
(e)the development is to be carried out—
(i)where approval has been given by the planning authority, within a period of 3 years from the date on which approval was given,
(ii)in any other case, within a period of 3 years from the date on which the planning authority were given the information referred to in paragraph (3)(b).
(5) In this class—
“principal elevation” means the elevation of the building which by virtue of its design or setting, or both, is the principal elevation,
“rear elevation” means the elevation of the building that is opposite its principal elevation,
“side elevation” means the elevation of the building linking the principal elevation with the rear elevation.”.
In terms of section 26(2)(a) of the Town and Country Planning (Scotland) Act 1997 (“the 1997 Act”) should the works to alter or replace an existing window only affect the interior of the building or would not materially affect the external appearance of the building those works would not for the purposes of the 1997 Act be taken to involve development.