6.—(1) Where there is a material change of use of the whole of a building, such work, if any, shall be carried out as is necessary to ensure that the building complies with the applicable requirements of the following paragraphs of Schedule 1—
(a)in all cases, B1 (means of warning and escape)
B2 (internal fire spread—linings)
B3 (internal fire spread—structure)
B4(2) (external fire spread—roofs)
B5 (access and facilities for the fire service)
C2(c) (interstitial and surface condensation)
F1 (ventilation)
G1 (cold water supply)
G3(1) to (3) (hot water supply and systems)
G4 (sanitary conveniences and washing facilities)
G5 (bathrooms)
G6 (kitchens and food preparation areas)
G2 (bathrooms)
H1 (foul water drainage)
H6 (solid waste storage)
J1 to J4 (combustion appliances)
L1 (conservation of fuel and power)
P1 (electrical safety);
(b)in the case of a material change of use described in regulation 5(c), (d), (e) or (f), A1 to A3 (structure);
(c)in the case of a building exceeding fifteen metres in height, B4(1) (external fire spread—walls);
(d)in the case of a material change of use described in regulation 5(a), (b), (c), (d), (g), (h), (i) or, where the material change provides new residential accommodation, (f), C1(2) (resistance to contaminants);
(e)in the case of a material change of use described in regulation 5(a), C2 (resistance to moisture);
(f)in the case of a material change of use described in regulation 5(a), (b), (c), (g), (h) or (i), E1 to E3 (resistance to the passage of sound);
(g)in the case of a material change of use described in regulation 5(e), where the public building consists of or contains a school, E4 (acoustic conditions in schools);
(h)in the case of a material change of use described in regulation 5(a) or (b), G2 (water efficiency) and G3(4) (hot water supply and systems: hot water supply to fixed baths);
(i)in the case of a material change of use described in regulation 5(c), (d), (e) or (j), M1 (access and use).
(2) Where there is a material change of use of part only of a building, such work, if any, shall be carried out as is necessary to ensure that—
(a)that part complies in all cases with any applicable requirements referred to in paragraph (1)(a);
(b)in a case in which sub-paragraphs (b), (e), (f), (g) or (h) of paragraph (1) apply, that part complies with the requirements referred to in the relevant sub-paragraph;
(c)in a case to which sub-paragraph (c) of paragraph (1) applies, the whole building complies with the requirement referred to in that sub-paragraph; and
(d)in a case to which sub-paragraph (i) of paragraph (1) applies—
(i)that part and any sanitary conveniences provided in or in connection with that part comply with the requirements referred to in that sub-paragraph; and
(ii)the building complies with requirement M1(a) of Schedule 1 to the extent that reasonable provision is made to provide either suitable independent access to that part or suitable access through the building to that part.