B 34
[Subsidiary]
L.N. 294/76.
Areas, etc. to be paved. L.N. 294/76.
Certain floors to be impermeable.
Lowest floor to be above ground level. L.N. 294/76.
Ventilation below wood floors. L.N. 294/76.
CAP. 123]
Building (Construction) Regulations
[1985 Ed.
(4) Where in any part of a building the floor next above the ground is constructed of plain or reinforced concrete, constructed so as to leave between it and the ground an air space, ventilated in accordance with paragraph (5) and enclosed so as to prevent its use for any other purpose, such floor may be deemed to be the layer of concrete required by paragraph (1).
(5) (a) An enclosed space under a floor shall be ventilated on at least 2 sides with air-bricks or otherwise, having an open area of not less than the equivalent of 4,000 mm2/m of external wall. No single opening in any such air-brick or ventilator shall exceed 5 mm in its least dimension.
(b) Where the flow of air may be obstructed in places by solid construction, ducts of a total area equal to not less than 2 times the total area of the opening in the air-bricks or other ventilator in the external walls shall be formed in such solid construction.
41. (1) The ground surface of every area, back yard or alleyway of every building (unless exempted as a garden) shall be covered with
(a) a layer of concrete not less than 100 mm thick and not inferior to Grade V;
(b) stone or brick paving bedded and jointed in cement mortar;
(c) a layer of bituminous macadam 75 mm thick finished smooth with a stopping of fine bituminous macadam 25 mm thick; or
(d) a layer of such other impervious material as the Building Authority may approve.
(2) Such surface covering shall be laid to fall at a gradient of not less than 1 in 80 to a gulley trap or drainage channels connected to a surface water drain.
42. The floor of every room to which a water supply is provided shall be constructed of concrete or such other impermeable material as the Building Authority may approve.
43. The level of the floor next above the ground of every building shall be not less than 150 mm above the level of the surface of the external ground, paving or oversite concrete at the entrance to that floor.
44. (1) Where in any part of a building the floor next above the ground is constructed of wood, it shall be so constructed as to leave an air-space not less than 225 mm deep between the level of the underside of the joists and the level of the upper surface of the layer of concrete required by regulation 40(1) and that space shall be so ventilated as to comply with the requirements of regulation 40(5).