O-1954-476 - Laserfiche WebLink

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--- e , -, " . . -33- (4) Where walls of hollow masonry units are decreased in thickness, a course of solid masonry l3hall be interposed between the wall below and the thinner wall above, or the hollow llnit~ in the top course of the thicker wall shall be filled solidly with mortar or masonry. (d) Bearing: In walls and piers of ho:l;lCl'N masonry units, suitable pro- vision shall be made for proper bearing at the ends of all beams and at points of load concentration. 6. CAVITY WALLS AND HOLLCJ1 \VALIS. (a) Height and thickness. (1) Cavity walls and hollow walls shall not exceed 35 feet in height. Gavity walls, exclusive of .he cavity, and hollow walls shall not be less in thick- ness than required for solid masonry walls in subsection 3 of this section. (2) In cavity waJls, neither the facing nor backing shall be less than ;1 3/4 inches in nominal thickness and the cavity shall be not less than 2 inches nor more than 3 inches in width. (b) Lateral support. Cavity walls shall be supported a.t right angles to the wall face at intervalB not exceeding 14 times, and hollow walls at intervals not exceeding 18 times the nl)minalwall thiclmess. Such lateral support shall con- I',orm to subsection 10 of thin section. (c) Bond. (1) In hollow walls the parts of same shall be connected by bonds of brick, stone or the ma~erial of the walls, placed not mer e than 24 inches apart in either direction; but the parts shall not be deemed to act together in th.e support of loads unless such bonds are of a size and design to fully develop the strength of either pa rt. (2) In cavity wall:3 the facing and backing shall be securely tied together with suitable bonding ties of ad~quate strength. A 3/16 inch diameter stt~el rod or metal tie of equ:.valent stiffness coated with a noncorroding metal or other approved protective coating shall be used for each 3 square feet of wall surface. 'ffuere hollor. masoIlI'jo units are laid with the cells vertical, rectangular tie!s shall be used; in other 'Wa~ls the ends of ties shall be bent to 90 degree angles to provide hooks not less than 2 inches long. Ties shall be embedded in horizontal joints of facing ani backing. Additional bonding ties shall be pro- vid.ed at all openings, spaced :lot more than 3 feet apart around the perimeter and TIithin 12 inches of the opening. Cavity walls of plain concrete shall be reinforced as provided for solid '\'Talls of plain concrete in subsection 9 of this section.