Tempo:
Table 17 Maximum spans for built-up floor beams supporting not more than three floors1, 2
Commercial Designation Douglas Fir – Larch
Grade No. 1 and No. 2
Hem – Fir
No. 1 and No. 2
Spruce – Pine – Fir
No. 1 and No. 2
Supported Length, m5, 6 ft. 2.4 8 3.0 10 3.6 12 4.2 14 4.8 16 5.4 18 6.0 20 2.4 8 3.0 10 3.6 12 4.2 14 4.8 16 5.4 18 6.0 20 2.4 8 3.0 10 3.6 12 4.2 14 4.8 16 5.4 18 6.0 20
Maximum Span, m (ft.–in.)3, 4 Size of Built-up Beam, mm (in.) 38 x 184 38 x 235 38 x 286 2x8 2 x 10 2 x 12 3-ply 4-ply 5-ply 3-ply 4-ply 5-ply 3-ply 4-ply 5-ply 1.85 6–0 1.66 5–5 1.51 4–11 1.40 4–7 1.31 4–3 1.23 4–0 1.17 3–10 1.94 6–4 1.74 5–8 1.58 5–2 1.43 4–8 1.30 4–2 1.19 3–10 1.11 3–7 2.01 6–7 1.80 5–10 1.64 5–4 1.52 4–11 1.40 4–6 1.28 4–2 1.19 3–10
2.14 6–11 1.91 6–3 1.74 5–8 1.62 5–3 1.51 4–11 1.42 4–8 1.35 4–5 2.24 7–4 2.00 6–6 1.83 5–11 1.69 5–6 1.58 5–2 1.47 4–9 1.36 4–5 2.32 7–7 2.08 6–9 1.90 6–2 1.75 5–9 1.64 5–4 1.55 5–0 1.47 4–9
2.39 7–9 2.14 6–11 1.95 6–4 1.81 5–11 1.69 5–6 1.59 5–2 1.51 4–11 2.51 8–2 2.24 7–4 2.05 6–8 1.89 6–2 1.77 5–9 1.67 5–5 1.58 5–2 2.60 8–5 2.32 7–7 2.12 6–11 1.96 6–5 1.84 6–0 1.73 5–8 1.64 5–4
2.26 7–4 2.02 6–7 1.85 6–0 1.71 5–7 1.60 5–3 1.51 4–11 1.43 4–8 2.37 7–9 2.12 6–11 1.92 6–3 1.71 5–7 1.56 5–1 1.44 4–8 1.34 4–4 2.46 8–0 2.20 7–2 2.01 6–6 1.85 6–0 1.68 5–5 1.54 5–0 1.44 4–8
2.61 8–6 2.34 7–7 2.13 6–11 1.98 6–5 1.85 6–0 1.74 5–8 1.65 5–5 2.74 8–11 2.45 8–0 2.24 7–3 2.07 6–9 1.92 6–3 1.76 5–8 1.63 5–3 2.84 9–3 2.54 8–3 2.32 7–7 2.15 7–0 2.01 6–6 1.89 6–2 1.76 5–8
2.92 9–6 2.61 8–6 2.39 7–9 2.21 7–2 2.07 6–9 1.95 6–4 1.85 6–0 3.06 10–0 2.74 8–11 2.50 8–2 2.32 7–6 2.17 7–1 2.04 6–8 1.92 6–3 3.17 10–4 2.84 9–3 2.59 8–5 2.40 7–10 2.24 7–4 2.12 6–11 2.01 6–6
2.63 8–7 2.35 7–8 2.14 7–0 1.99 6–6 1.86 6–1 1.75 5–8 1.66 5–5 2.75 9–0 2.46 8–0 2.18 7–1 1.95 6–4 1.77 5–9 1.64 5–4 1.53 5–0 2.85 9–3 2.55 8–4 2.33 7–7 2.10 6–10 1.91 6–2 1.76 5–9 1.64 5–4
3.03 9–10 2.71 8–10 2.48 8–1 2.29 7–6 2.14 7–0 2.02 6–7 1.92 6–3 3.18 10–4 2.84 9–3 2.60 8–5 2.40 7–10 2.18 7–1 2.00 6–6 1.85 6–0 3.29 10–9 2.95 9–7 2.69 8–9 2.49 8–1 2.33 7–7 2.16 7–0 2.00 6–6
3.39 11–0 3.03 9–10 2.77 9–0 2.56 8–4 2.40 7–10 2.26 7–4 2.14 7–0 3.56 11–7 3.18 10–4 2.90 9–5 2.69 8–9 2.51 8–2 2.35 7–8 2.18 7–1 3.68 12–0 3.29 10–9 3.01 9–9 2.78 9–1 2.60 8–6 2.46 8–0 2.33 7–7
Continued on p. 281
Commercial Designation Douglas Fir – Larch
Grade No. 1 and No. 2
Hem – Fir
No. 1 and No. 2
Spruce – Pine – Fir
No. 1 and No. 2
Supported Length, m5, 6 ft. 2.4 8 3.0 10 3.6 12 4.2 14 4.8 16 5.4 18 6.0 20 2.4 8 3.0 10 3.6 12 4.2 14 4.8 16 5.4 18 6.0 20 2.4 8 3.0 10 3.6 12 4.2 14 4.8 16 5.4 18 6.0 20
Maximum Span, m (ft.–in.)3, 4 Size of Built-up Beam, mm (in.) 38 x 184 38 x 235 38 x 286 2x8 2 x 10 2 x 12 3-ply 4-ply 5-ply 3-ply 4-ply 5-ply 3-ply 4-ply 5-ply 1.85 6–0 1.66 5–5 1.51 4–11 1.40 4–7 1.31 4–3 1.23 4–0 1.17 3–10 1.94 6–4 1.74 5–8 1.58 5–2 1.43 4–8 1.30 4–2 1.19 3–10 1.11 3–7 2.01 6–7 1.80 5–10 1.64 5–4 1.52 4–11 1.40 4–6 1.28 4–2 1.19 3–10
2.14 6–11 1.91 6–3 1.74 5–8 1.62 5–3 1.51 4–11 1.42 4–8 1.35 4–5 2.24 7–4 2.00 6–6 1.83 5–11 1.69 5–6 1.58 5–2 1.47 4–9 1.36 4–5 2.32 7–7 2.08 6–9 1.90 6–2 1.75 5–9 1.64 5–4 1.55 5–0 1.47 4–9
2.39 7–9 2.14 6–11 1.95 6–4 1.81 5–11 1.69 5–6 1.59 5–2 1.51 4–11 2.51 8–2 2.24 7–4 2.05 6–8 1.89 6–2 1.77 5–9 1.67 5–5 1.58 5–2 2.60 8–5 2.32 7–7 2.12 6–11 1.96 6–5 1.84 6–0 1.73 5–8 1.64 5–4
2.26 7–4 2.02 6–7 1.85 6–0 1.71 5–7 1.60 5–3 1.51 4–11 1.43 4–8 2.37 7–9 2.12 6–11 1.92 6–3 1.71 5–7 1.56 5–1 1.44 4–8 1.34 4–4 2.46 8–0 2.20 7–2 2.01 6–6 1.85 6–0 1.68 5–5 1.54 5–0 1.44 4–8
2.61 8–6 2.34 7–7 2.13 6–11 1.98 6–5 1.85 6–0 1.74 5–8 1.65 5–5 2.74 8–11 2.45 8–0 2.24 7–3 2.07 6–9 1.92 6–3 1.76 5–8 1.63 5–3 2.84 9–3 2.54 8–3 2.32 7–7 2.15 7–0 2.01 6–6 1.89 6–2 1.76 5–8
2.92 9–6 2.61 8–6 2.39 7–9 2.21 7–2 2.07 6–9 1.95 6–4 1.85 6–0 3.06 10–0 2.74 8–11 2.50 8–2 2.32 7–6 2.17 7–1 2.04 6–8 1.92 6–3 3.17 10–4 2.84 9–3 2.59 8–5 2.40 7–10 2.24 7–4 2.12 6–11 2.01 6–6
2.63 8–7 2.35 7–8 2.14 7–0 1.99 6–6 1.86 6–1 1.75 5–8 1.66 5–5 2.75 9–0 2.46 8–0 2.18 7–1 1.95 6–4 1.77 5–9 1.64 5–4 1.53 5–0 2.85 9–3 2.55 8–4 2.33 7–7 2.10 6–10 1.91 6–2 1.76 5–9 1.64 5–4
3.03 9–10 2.71 8–10 2.48 8–1 2.29 7–6 2.14 7–0 2.02 6–7 1.92 6–3 3.18 10–4 2.84 9–3 2.60 8–5 2.40 7–10 2.18 7–1 2.00 6–6 1.85 6–0 3.29 10–9 2.95 9–7 2.69 8–9 2.49 8–1 2.33 7–7 2.16 7–0 2.00 6–6
3.39 11–0 3.03 9–10 2.77 9–0 2.56 8–4 2.40 7–10 2.26 7–4 2.14 7–0 3.56 11–7 3.18 10–4 2.90 9–5 2.69 8–9 2.51 8–2 2.35 7–8 2.18 7–1 3.68 12–0 3.29 10–9 3.01 9–9 2.78 9–1 2.60 8–6 2.46 8–0 2.33 7–7
Continued on p. 281
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