14
Chimney shafts.
Open
cooking
Blabs to
BUILDING (CONSTRUCTION) REGULATIONS, 1956
(i) distant at least 6 inches measured horizontally and 12 inches measured vertically from that fireplace open- ing; and
(ii) solidly backed with incombustible material.
70. Every chimney shaft shall comply with the following provisions :
(1) If built of bricks-
(a) it shall be constructed of suitable solid bricks jointed
with suitable mortar;
(b) it shall be square, circular, or of any regular poly- gonal shape, and the outer face shall be built to a batter of at least 24 inches in every ro feet of height; (c) the height measured from the base to the top of the chimney shaft, shall not exceed the least width of the base multiplied by-
(1) 10 times if the shaft be square;
(ii) 12 times if the shaft be circular or polygonal; (d) the thickness at the top, and for 20 feet below the
top shall be at least 82 inches;
(e) for the purpose of this regulation, the expression "base" means the underside of the course immedi- ately above the footings, if any, or if there are none, the bottom of the chimney shaft.
(2) If built of reinforced concrete, it shall comply with the provisions of Part IX. (Structural Use of Reinforced Concrete) of these regulations.
(3) If built of mild steel shall be constructed of steel plates not less than 3/16 inches thick and properly stayed and protected against corrosion.
(4) Any internal lining shall be additional to the thickness
of the chimney and shall not be bonded therewith,
71. (0) Every open cooking slab (not being a fireplace and not directly connected to a chimney) constructed or adapted for have boods. the use of coal, charcoal or wood as fuel shall be provided with an incombustible hood of sheet metal or other material as the Building Authority may approve, connecting with a chimney.
BUILDING (CONSTRUCTION) REGULATIONS, 1956
15
(2) The bottom edge of such hood shall be not more than 6 feet above floor level and shall cover the area of the cooking slab.
12. No floor ur roof of combustible material shall be con- Cellings
over fire- structed over any fireplace, heating appliance or oven, burning
places to solid fuel or oil fuel, within five feet of the top of such fireplace, be pro-
tected. heating appliance or oven, unless protected with a lining of incombustible material not less than 3/16 inches thick, covering a horizontal area of not less than 100 square feet and so arranged as to give the most effective protection,
PART VIII.
Roots.
Govere).
73. (#) The roof of every building and of any minor Roofs structure placed above such roof except the doors, and frames to be of dormers or sky lights shall be covered with tiles, glass, metal, or other incombustible material:
Provided that where a roof is constructed entirely of incom- bustible materials the external covering may consist of
(a) rock asphalt containing not more than 17 per cent by
weight of bitumen; or
(b) a layer or layers of compressed and impervious felt membrane roofing having an aggregate thickness of not more than inch bedded down solidly on the roof by viscous materials.
(2) Where the roof is covered in the manner provided by sub-regulation (1) (b) and the slope thereof exceeds zo degrees with the horizontal, the external layer of such roofing shall be surfaced with a mineral dressing.
74. Every roof shall be-
(a) weatherproof; and
(b) provided with adequate gutters and rain water pipes to prevent the direct discharge of water upon or over any footpath or roadway.
Roofs to be weather proof.