—(1) Subject to the following provisions of this section, in this Act, except where the context otherwise requires, "development" means the carrying out of any building, engineering, mining, earthworks or other operations in, on, over or under land, or to the making of any material change in the use of any building or land, and "develop" and "developing" shall be construed accordingly.
(2) The following operations or uses of land shall not be deemed for the purposes of this Act to involve development of land:
the carrying out of works for the maintenance, improvement or other alteration of a building which do not materially affect the external appearance or the floor area of the building;
the carrying out of such minor or preliminary works and such temporary use of land as may be declared by the competent authority for the purpose of this subsection;
the carrying out by any statutory authority of any works on land within the boundaries of a street, being works which are necessary for the maintenance or improvement of the street;
the carrying out by any statutory authority of any works for the purpose of laying, inspecting, repairing or renewing any sewers, mains, pipes, cables or other apparatus, including the breaking open of any street or other land for that purpose;
the carrying out of any act authorised or required by the Destruction of Disease-Bearing Insects Act (Cap.79);
the use of any existing building or land within the curtilage of a dwelling-house for any purpose incidental to the enjoyment of the dwelling-house as such;
the use of any land for the purposes of agriculture or forestry (including afforestation) and the use for any of those purposes of any building occupied together with land so used;
in the case of buildings or land which are used for a purpose of any class specified in any rules made under section 61, the use of the building or land or any part thereof for any other purpose within the same class.
(3) For the avoidance of doubt, it is hereby declared that for the purposes of this section —
the use as 2 or more separate houses of any building previously used as a single house involves a material change in the use of the building and of each part thereof which is so used;
the use as a dwelling-house of any building not originally constructed for human habitation involves a material change in the use of the building;
the use for other purposes of a building or part of a building originally constructed as a dwelling-house involves a material change in the use of the building;
the demolition or reconstruction of or addition to a building constitutes development;
the use for the display of advertisements of any external part of a building which is not normally used for that purpose involves a material change in the use of the building;
the deposit of refuse or waste materials on land involves a material change in the use thereof notwithstanding that the land is comprised in a site already used for that purpose, if —
the superficial area of the deposit is extended; or
the height of the deposit is extended and exceeds the level of the land adjoining the site;
subject to subsection (2)(h), the use of any building or part thereof for any purpose other than that for which the building was originally constructed involves a material change in the use of the building; and
any decorative, painting, renovation or building works, whether external or internal, to or on a monument in respect of which there is in force a preservation order under the Preservation of Monuments Act (Cap.239) shall constitute building operations.