35.—(1) A building shall be so designed and constructed that, in the event of a fire, its stability will be retained for a reasonable period.
(2) A wall common to two or more buildings shall be so designed and constructed that it provides adequate resistance to the spread of fire between those buildings and for the purposes of this paragraph a dwellinghouse in a terrace and a semi-detached dwellinghouse shall be considered as a separate building.
(3) To inhibit the spread of fire within it, a building shall be adequately sub-divided with fire-resisting construction.
(4) A building shall be so designed and constructed that the spread of fire (and in particular smoke) within concealed spaces in its structure and fabric is adequately inhibited.