B 40
[Subsidiary]
Thickness of walls where difference in ground levels.
L.N. 294/76.
(Cap. 123, sub. leg.)
Thickness of external walls of certain small buildings.
L.N. 294/76.
Cavity walls. L.N. 294/76.
CAP. 123] Building Construction) Regulations
[1985 Ed.
(2) The projection of any corbelling shall not exceed 1/3 of the thickness of the wall immediately below that corbelling.
58. (1) Where the level of the ground or of the surface of the site concrete is different on 1 side of a wall to that on the other, the width of such wall in a building built of bricks or building blocks shall be not less than 1/4 of such difference of level.
(2) If such difference in level exceeds 1.8 m, the wall shall be designed and built as a retaining wall and in accordance with regulation 48 of the Building (Planning) Regulations.
59. (1) Subject to the provisions of paragraph (2)---
(a) a 1-storey building, other than a domestic building, whose width measured in the direction of the span of the roof does not exceed 9 m and the height of whose walls does not exceed 3 m; or
(b) a garage, greenhouse, store, water-closet or other room (attached to a domestic building) not intended to be used for habitation and not exceeding 3 m in height,
may have external walls not less than 100 mm thick.
(2) (a) Where any such wall exceeds 2.5 m either in height or length it shall be bonded into piers, 1 of which shall be placed at each end of the wall, not less than 225 mm square in horizontal section, or of such greater size as may be required to give adequate stability.
(b) Where any such wall exceeds 3 m in length additional such piers shall be placed in the wall so as to divide the same into lengths not exceeding 3 m.
(c) All bedding and jointing in such walls and piers shall be in cement mortar.
(d) Such walls shall bear no load other than the distributed load of the roof, which shall be so constructed that the walls are not subject to any lateral thrust therefrom.
60. (1) A load-bearing external or party wall not exceeding 7 m in height and 9 m in length in a building other than a public building or a building of the warehouse class, and, subject to the provisions of regulation 68 a panel wall in any building, may be constructed as a cavity wall.
(2) No storey in a building of cavity wall construction shall exceed a height of 3.5 m.
(3) Cavity walls shall be constructed of solid bricks or building blocks properly bedded and jointed in cement mortar, and shall comprise 2 leaves, each not less than 100 mm thick and an intervening cavity not less than 50 mm and not more than 75 mm wide.
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