(1) Spans and sizes of wood lintels shall conform to the spans shown in Tables A-12 to A-16,
(a) for buildings of residential occupancy,
(b) where the wall studs exceed 38 mm by 64 mm in size,
(c) where the spans of supported joists do not exceed 4.9 m, and
(d) where the spans of trusses do not exceed 9.8 m.
(2) In loadbearing exterior and interior walls of 38 mm by 64 mm framing members, lintels shall consist of,
(a) solid 64 mm thick members on edge, or
(b) 38 mm thick and 19 mm thick members fastened together with a double row of nails not less than 63 mm long and spaced not more than 450 mm apart.
(3) Lintels referred to in Sentence (2),
(a) shall be not less than 50 mm greater in depth than those shown in Tables A-12 to A-16 for the maximum spans shown, and
(b) shall not exceed 2.24 m in length.