For regulation 22 substitute—

“Interpretation22.

In this Part—

“External wall” of a building includes reference to—

(a)

anything located within any space forming part of the wall;

(b)

any decoration or other finish applied to any external (but not internal) surface forming part of the wall;

(c)

any windows and doors in the wall; and

(d)

any part of a roof pitched at an angle of more than 70° to the horizontal if that part of the roof adjoins a space within the building to which persons have access, but not access only for the purpose of carrying out repairs or maintenance.

“Harmful substances” includes fumes and vapours;

“Relevant work” means—

(a)

the erection of a building;

(b)

the structural alteration or extension of a building;

(c)

the provision of any service or fitting; or

(d)

the backfilling of any excavation carried out in connection with (a), (b) or (c); and

“Specified attachment” means—

(a)

a balcony attached to an external wall;

(b)

a device for reducing heat gain within a building by deflecting sunlight which is attached to an external wall; or

(c)

a solar panel attached to an external wall.”.

For regulation 23 substitute—

“Fitness of materials and workmanship23.

(1)

In any relevant work—

(a)

the materials used shall—

(i)

be of a suitable nature and quality in relation to the purposes for and the conditions in which they are used;

(ii)

be adequately mixed and prepared;

(iii)

be applied, used or fixed so as adequately to perform the functions for which they are designed; and

(iv)

not continue to emit any harmful substance longer than is reasonable in the circumstances; and

(b)

the standards of materials and workmanship need be no more than are necessary to—

(i)

secure the health, safety, welfare and convenience of persons in or about the building; and

(ii)

further the conservation of fuel and power.

(2)

Subject to paragraph (3), building work shall be carried out so that materials which become part of an external wall, or specified attachment, of a relevant building are of European Classification A2-s1, d0 or Class A1, classified in accordance with BS EN 13501-1:2018.

(3)

Paragraph (2) does not apply to—

(a)

cavity trays when used between two leaves of masonry;

(b)

any part of a roof (other than any part of a roof which falls within paragraph (d) of the definition of ‘External wall’ in regulation 22), if that part is connected to an external wall;

(c)

door frames and doors;

(d)

electrical installations;

(e)

insulation and water proofing materials used below ground level;

(f)

intumescent and fire stopping materials where the inclusion of the materials is necessary to meet the requirements of Part E;

(g)

membranes;

(h)

seals, gaskets, fixings, sealants and backer rods;

(i)

thermal break materials where the inclusion of the materials is necessary to meet thermal bridging requirements of Part F; or

(j)

window frames and glass.

(4)

In this regulation—

(a)

a “relevant building” means a building with a storey (not including roof-top plant areas or any storey consisting exclusively of plant rooms) at least 18 m above ground level and which—

(i)

contains one or more dwellings;

(ii)

contains an institution; or

(iii)

contains a room for residential purposes (excluding any room in a hostel, hotel or boarding house); and

(b)

“above ground level”, in relation to a storey, means above ground level when measured from the lowest ground level adjoining the outside of a building to the top of the floor surface of the storey.”.