8. For regulation 28 (and the heading before it) substitute—
28.—(1) Paragraph (3) applies to an existing building with a total useful floor area over 1000m2 where the proposed building work consists of or includes—
(a)the initial provision of any fixed building services; or
(b)an increase to the installed capacity of any fixed building services.
(2) Paragraph (3) applies to an existing building where the proposed building work consists of or includes—
(a)an extension; or
(b)the extension of the building’s heating system or the provision of a fixed heating appliance, to heat a previously unheated space.
(3) Subject to paragraph (4), where this paragraph applies, such work, if any, shall be carried out as is necessary to ensure that the building complies with the requirements of Part L of Schedule 1.
(4) Nothing in paragraph (3) requires work to be carried out if it is not technically, functionally and economically feasible.”