(a) All exterior wood stud walls shall have the strength and rigidity equivalent to two inch by four inch studs, spaced sixteen inches o.c., securely fastened to plates, top and bottom, and diagonally braced at corners with one inch by four inch braces let into the outside faces of the studs at approximately forty-five degrees and extending from the wall to the plate. However, the studding in the exterior walls of accessory buildings, and of one-story dwellings, may be spaced not more than twenty-four inches o.c. Braces shall extend in opposite directions on each side of the corner and shall be securely nailed to each stud and to the sill and plate. When openings occur near the corners, one inch by four inch knee braces let into the outside face of the stud shall be installed above and below the openings at approximately forty-five degrees and extend across not less than three studs.
Corner bracing may be omitted when good sheathing is used, laid diagonally at an approximate angle of forty-five degrees and extending in opposite directions on each side of the corners. All bracing may be omitted when four foot by eight-foot sheets of plywood or approved insulation boards are used.
(b) Exterior wood stud walls shall have corner posts either built-up or solid, not less than three two by fours in section.
(c) Studs in exterior frame walls may run from the sill to the roof line, provided they do not exceed twenty feet in length, but such studs shall be in continuous length without splicing. Floor joists supported on exterior frame walls shall bear on one by six-inch ribbons let into the inside face of the studs. Where the wall height exceeds twenty feet, a doubled two-inch by four-inch bearing plate shall be installed continuously at the second floor level.
(d) Top plates shall be not less than doubled two by fours, which shall lap at all corners and at all intersecting partitions. All such laps shall be securely spiked. Top plates shall be nailed on one at a time. The first plate shall be nailed with two 16d common nails to each stud and the second or upper top plate shall be nailed every sixteen inches between studs. Where plates are cut or notched, the same shall be adequately reinforced.
(e) All bearing plates for roof rafters framing onto masonry walls shall be bolted to the masonry walls with one-half inch by eighteen-inch bolts, bedded firmly in the masonry and spaced not more than eight feet apart.
(NOTE: When masonry occurs directly over a joist or rafter extending in a wall, wood plates shall not be used, but the joist or rafter shall bear on not less than four inches of solid masonry and be anchored.)
(f) When studding does not bear directly on the foundation wall plate, such studding shall have full bearing on a foot plate of the same thickness and width as the studding and such plate shall be continuous, except where omissions are necessary to provide for wall openings, ducts, etc. Foot plates shall bear over the full width of the upright of the sill and shall be nailed to each joist with not less than one 16d common nail when joists bear on the wall or plate below, and with one 16d common nail for each sixteen inches of length of the plate where joists run parallel to the plate. The bottom of all studs shall be toe-nailed into the plate with not less than four 8d common nails.
(g) For ordinary conditions of framing, all exterior stud frame walls shall be sheathed or tongued and grooved, or shiplap siding not less than three-quarters of an inch thick (actual) shall be used. When wood sheathing is laid diagonally, it shall be applied at approximately 45 degrees and extend in opposite directions on each side adjoining at a corner, and the corner bracing shall not be required in such cases.
(h) For ordinary conditions of framing, wood sheathing boards shall not be less than five-eighths of an inch thick applied solid with each board drawn up tight and securely nailed at each stud or bearing point. If boards less than ten inches are used, they shall be double nailed, and if boards ten inches and over are used, nails shall not be more than four inches center to center with not less than three nails for a ten-inch board at each stud or bearing point. Jointing shall occur over the center of the parallel to the studs. Any other structural sheathing material may be used in frame construction which, when subjected to a wall racking test approved equal to that of the Forest Products Laboratory of the United States Department of Agriculture, Forest Service, develops a strength and rigidity equivalent or better than that of horizontal wood sheathing as above specified.
(NOTE: End-notched (T & G) boards may be used for sheathing, provided that no two adjoining boards break joints over the same stud space, and that each board shall bear on at least two studs.)
(i) Wood sheathing used in connection with stucco finish shall be applied horizontally and the frame shall be substantially braced.
(j) When shingles are applied over other than wood sheathing boards, one by two-inch nailing strips shall be used, nailed to the studs over the building paper and spaced according to the shingle exposure.
(k) Wood sheathing boards shall be installed and laid close under rigid shingle siding where the shingle butt thickness is less than three-eighths of an inch.
(l) All sheathing shall be covered on the exterior side with water-resisting building paper or saturated asphalt felt, or be adequately treated to repel moisture. When such paper or felt is used, each lap shall be not less than four inches with not less than a four-inch lap on water-resisting material around openings. All exterior openings in frame walls shall have strips of water-resisting building paper or saturated asphalt felt installed behind the exterior trim, unless adequate provision is made against water penetration.
(m) Plywood wall sheathing may be installed horizontally or vertically. When plywood is applied horizontally, vertical joints shall be staggered at least one stud space. In two-story construction, rows of solid blocking shall be installed behind the horizontal joints to provide edge nailing. Minimum plywood thickness shall be five-sixteenths of an inch applied to studs sixteen inches on center.
(n) Plywood panel siding may be applied directly over the studs, provided they are not less than three-eighths of an inch nominal, except for “303 Siding” panels which are grooved, striated, brushed or have another texture surface. Average thickness of “303 Siding” panels after texturing shall be not less than five-sixteenths of an inch.
(o) Except as otherwise required, all parts of the wooden frame work shall be kept not less than eight inches above the ground level unless adequate protection against deterioration because of moisture is provided.
(Ord. 42-1981. Passed 2-23-81.)