12.0 7-10 8- 1 8- 5 8- 8 8-11 9- 2 9- 5 9- 8 9-10 10- 0 10- 3 10- 5 10- 7 10- 9 10-11 11- 1 11- 3
16.0 7- 1 7- 5 7- 8 7-11 8- 1 8- 4 8- 7 8- 9 8-11 9- 1 9- 4 9- 6 9- 8 9- 9 9-11 10- 1 10- 3
2x 4 19.2 6- 8 6-11 7- 2 7- 5 7- 8 7-10 8- 1 8- 3 8- 5 8- 7 8- 9 8-11 9- 1 9- 3 9- 4 9- 6 9- 8
24.0 6- 2 6- 5 6- 8 6-11 7- 1 7- 3 7- 6 7- 8 7-10 8- 0 8- 1 8- 3 8- 5 8- 7 8- 8 8-10 8-11
12.0 12- 3 12- 9 13- 3 13- 8 14- 1 14- 5 14- 9 15- 2 15- 6 15- 9 16- 1 16- 4 16- 8 16-11 17- 2 17- 5 17- 8
16.0 11- 2 11- 7 12- 0 12- 5 12- 9 13- 1 13- 5 13- 9 14- 1 14- 4 14- 7 14-11 15- 2 15- 5 15- 7 15-10 16- 1
2x 6 19.2 10- 6 10-11 11- 4 11- 8 12- 0 12- 4 12- 8 12-11 13- 3 13- 6 13- 9 14- 0 14- 3 14- 6 14- 8 14-11 15- 2
24.0 9- 9 10- 2 10- 6 10-10 11- 2 11- 5 11- 9 12- 0 12- 3 12- 6 12- 9 13- 0 13- 3 13- 5 13- 8 13-10 14- 1
12.0 16- 2 16-10 17- 5 18- 0 18- 6 19- 0 19- 6 19-11 20- 5 20-10 21- 2 21- 7 21-11 22- 4 22- 8 23- 0 23- 4
16.0 14- 8 15- 3 15-10 16- 4 16-10 17- 3 17- 9 18- 1 18- 6 18-11 19- 3 19- 7 19-11 20- 3 20- 7 20-11 21- 2
2x 8 19.2 13-10 14- 5 14-11 15- 5 15-10 16- 3 16- 8 17- 1 17- 5 17- 9 18- 1 18- 5 18- 9 19- 1 19- 5 19- 8 19-11
24.0 12-10 13- 4 13-10 14- 3 14- 8 15- 1 15- 6 15-10 16- 2 16- 6 16-10 17- 2 17- 5 17- 9 18- 0 18- 3 18- 6
12.0 20- 8 21- 6 22- 3 22-11 23- 8 24- 3 24-10 25- 5 26- 0
16.0 18- 9 19- 6 20- 2 20-10 21- 6 22- 1 22- 7 23- 1 23- 8 24- 1 24- 7 25- 0 25- 5 25-10
2x10 19.2 17- 8 18- 4 19- 0 19- 7 20- 2 20- 9 21- 3 21- 9 22- 3 22- 8 23- 1 23- 7 23-11 24- 4 24- 9 25- 1 25- 5
24.0 16- 5 17- 0 17- 8 18- 3 18- 9 19- 3 19- 9 20- 2 20- 8 21- 1 21- 6 21-10 22- 3 22- 7 22-11 23- 4 23- 8
Fb 12.0 896 969 1040 1108 1174 1239 1302 1363 1423 1481 1539 1595 1651 1706 1759 1812 1864
Fb 16.0 986 1067 1145 1220 1293 1364 1433 1500 1566 1631 1694 1756 1817 1877 1936 1995 2052
Fb 19.2 1048 1134 1216 1296 1374 1449 1522 1594 1664 1733 1800 1866 1931 1995 2058 2120 2181
Fb 24.0 1129 1221 1310 1396 1480 1561 1640 1717 1793 1866 1939 2010 2080 2149 2217 2283 2349
Note: The required bending design value, Fb, in pounds per square inch is shown at the bottom of each table and is applicable to all lumber sizes shown. Spans are shown in feet-inches and are limited to 26′ and less. Check sources of supply for availability of lumber in lengths greater than 20′.
TABLE R-2
RAFTERS WITH L/240 DEFLECTION LIMITATION
DESIGN CRITERIA:
Strength - Live Load of 30 psf plus
Dead Load of 10 psf determines the required bending design value.
Deflection - For 30 psf live load.
Limited to span in inches divided by 240.
Size Spacing
(in) (in) Rafter Bending Design Value, Fb, (psi)
300 400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200 2300 2400
12.0 6- 2 7- 1 7-11 8- 8 9- 5 10- 0 10- 8 11- 3 11- 9 12- 4 12-10 13- 3 13- 9 14- 2 14- 8 15- 1 15- 6 15-11
16.0 5- 4 6- 2 6-10 7- 6 8- 2 8- 8 9- 3 9- 9 10- 2 10- 8 11- 1 11- 6 11-11 12- 4 12- 8 13- 1 13- 5 13- 9 14- 1 14- 5
2x 6 19.2 4-10 5- 7 6- 3 6-10 7- 5 7-11 8- 5 8-11 9- 4 9- 9 10- 1 10- 6 10-10 11- 3 11- 7 11-11 12- 3 12- 7 12-10 13- 2 13- 6
24.0 4- 4 5- 0 5- 7 6- 2 6- 8 7- 1 7- 6 7-11 8- 4 8- 8 9- 1 9- 5 9- 9 10- 0 10- 4 10- 8 10-11 11- 3 11- 6 11- 9 12- 0 12- 4
12.0 8- 1 9- 4 10- 6 11- 6 12- 5 13- 3 14- 0 14-10 15- 6 16- 3 16-10 17- 6 18- 1 18- 9 19- 4 19-10 20- 5 20-11
16.0 7- 0 8- 1 9- 1 9-11 10- 9 11- 6 12- 2 12-10 13- 5 14- 0 14- 7 15- 2 15- 8 16- 3 16- 9 17- 2 17- 8 18- 1 18- 7 19- 0
2x 8 19.2 6- 5 7- 5 8- 3 9- 1 9- 9 10- 6 11- 1 11- 8 12- 3 12-10 13- 4 13-10 14- 4 14-10 15- 3 15- 8 16- 2 16- 7 16-11 17- 4 17- 9
24.0 5- 9 6- 7 7- 5 8- 1 8- 9 9- 4 9-11 10- 6 11- 0 11- 6 11-11 12- 5 12-10 13- 3 13- 8 14- 0 14- 5 14-10 15- 2 15- 6 15-10 16- 3
12.0 10- 4 11-11 13- 4 14- 8 15-10 16-11 17-11 18-11 19-10 20- 8 21- 6 22- 4 23- 1 23-11 24- 7 25- 4 26- 0
16.0 8-11 10- 4 11- 7 12- 8 13- 8 14- 8 15- 6 16- 4 17- 2 17-11 18- 8 19- 4 20- 0 20- 8 21- 4 21-11 22- 6 23- 1 23- 8 24- 3
2x10 19.2 8- 2 9- 5 10- 7 11- 7 12- 6 13- 4 14- 2 14-11 15- 8 16- 4 17- 0 17- 8 18- 3 18-11 19- 6 20- 0 20- 7 21- 1 21- 8 22- 2 22- 8
24.0 7- 4 8- 5 9- 5 10- 4 11- 2 11-11 12- 8 13- 4 14- 0 14- 8 15- 3 15-10 16- 4 16-11 17- 5 17-11 18- 5 18-11 19- 4 19-10 20- 3 20- 8
12.0 12- 7 14- 6 16- 3 17- 9 19- 3 20- 6 21- 9 23- 0 24- 1 25- 2
16.0 10-11 12- 7 14- 1 15- 5 16- 8 17- 9 18-10 19-11 20-10 21- 9 22- 8 23- 6 24- 4 25- 2 25-11
2x12 19.2 9-11 11- 6 12-10 14- 1 15- 2 16- 3 17- 3 18- 2 19- 0 19-11 20- 8 21- 6 22- 3 23- 0 23- 8 24- 4 25- 0 25- 8
24.0 8-11 10- 3 11- 6 12- 7 13- 7 14- 6 15- 5 16- 3 17- 0 17- 9 18- 6 19- 3 19-11 20- 6 21- 2 21- 9 22- 5 23- 0 23- 6 24- 1 24- 8 25- 2
E 12.0 0.15 0.23 0.32 0.43 0.54 0.66 0.78 0.92 1.06 1.21 1.36 1.52 1.69 1.86 2.04 2.22 2.41 2.60
E 16.0 0.13 0.20 0.28 0.37 0.47 0.57 0.68 0.80 0.92 1.05 1.18 1.32 1.46 1.61 1.76 1.92 2.08 2.25 2.42 2.60
E 19.2 0.12 0.18 0.26 0.34 0.43 0.52 0.62 0.73 0.84 0.95 1.08 1.20 1.33 1.47 1.61 1.75 1.90 2.05 2.21 2.37 2.53
E 24.0 0.11 0.16 0.23 0.30 0.38 0.46 0.55 0.65 0.75 0.85 0.96 1.08 1.19 1.31 1.44 1.57 1.70 1.84 1.98 2.12 2.27 2.41
Note: The required modulus of elasticity, E, in 1,000,000 pounds per square inch is shown at the bottom of each table, is limited to 2.6 million psi and less, and is applicable to all lumber sizes shown. Spans are shown in feet-inches and are limited to 26′ and less. Check sources of supply for availability of lumber in lengths greater than 20′.
TABLE R-3
RAFTERS WITH L/240 DEFLECTION LIMITATION
DESIGN CRITERIA:
Strength - Live Load of 40 psf plus
Dead Load of 10 psf determines the required bending design value.
Deflection - For 40 psf live load.
Limited to span in inches divided by 240.
Size Spacing
(in) (in) Rafter Bending Design Value, Fb, (psi)
300 400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200 2300 2400
12.0 5- 6 6- 4 7- 1 7- 9 8- 5 9- 0 9- 6 10- 0 10- 6 11- 0 11- 5 11-11 12- 4 12- 8 13- 1 13- 6 13-10 14- 2
16.0 4- 9 5- 6 6- 2 6- 9 7- 3 7- 9 8- 3 8- 8 9- 1 9- 6 9-11 10- 3 10- 8 11- 0 11- 4 11- 8 12- 0 12- 4 12- 7 12-11
2x 6 19.2 4- 4 5- 0 5- 7 6- 2 6- 8 7- 1 7- 6 7-11 8- 4 8- 8 9- 1 9- 5 9- 9 10- 0 10- 4 10- 8 10-11 11- 3 11- 6 11- 9 12- 0 12- 4
24.0 3-11 4- 6 5- 0 5- 6 5-11 6- 4 6- 9 7- 1 7- 5 7- 9 8- 1 8- 5 8- 8 9- 0 9- 3 9- 6 9- 9 10- 0 10- 3 10- 6 10- 9 11- 0
12.0 7- 3 8- 4 9- 4 10- 3 11- 1 11-10 12- 7 13- 3 13-11 14- 6 15- 1 15- 8 16- 3 16- 9 17- 3 17- 9 18- 3 18- 9
16.0 6- 3 7- 3 8- 1 8-11 9- 7 10- 3 10-10 11- 6 12- 0 12- 7 13- 1 13- 7 14- 0 14- 6 14-11 15- 5 15-10 16- 3 16- 7 17- 0
2x 8 19.2 5- 9 6- 7 7- 5 8- 1 8- 9 9- 4 9-11 10- 6 11- 0 11- 6 11-11 12- 5 12-10 13- 3 13- 8 14- 0 14- 5 14-10 15- 2 15- 6 15-10 16- 3
24.0 5- 2 5-11 6- 7 7- 3 7-10 8- 4 8-11 9- 4 9-10 10- 3 10- 8 11- 1 11- 6 11-10 12- 2 12- 7 12-11 13- 3 13- 7 13-11 14- 2 14- 6
12.0 9- 3 10- 8 11-11 13- 1 14- 2 15- 1 16- 0 16-11 17- 9 18- 6 19- 3 20- 0 20- 8 21- 4 22- 0 22- 8 23- 3 23-11
16.0 8- 0 9- 3 10- 4 11- 4 12- 3 13- 1 13-10 14- 8 15- 4 16- 0 16- 8 17- 4 17-11 18- 6 19- 1 19- 7 20- 2 20- 8 21- 2 21- 8
2x10 19.2 7- 4 8- 5 9- 5 10- 4 11- 2 11-11 12- 8 13- 4 14- 0 14- 8 15- 3 15-10 16- 4 16-11 17- 5 17-11 18- 5 18-11 19- 4 19-10 20- 3 20- 8
24.0 6- 6 7- 7 8- 5 9- 3 10- 0 10- 8 11- 4 11-11 12- 6 13- 1 13- 7 14- 2 14- 8 15- 1 15- 7 16- 0 16- 6 16-11 17- 4 17- 9 18- 1 18- 6
12.0 11- 3 13- 0 14- 6 15-11 17- 2 18- 4 19- 6 20- 6 21- 7 22- 6 23- 5 24- 4 25- 2 26- 0
16.0 9- 9 11- 3 12- 7 13- 9 14-11 15-11 16-10 17- 9 18- 8 19- 6 20- 3 21- 1 21- 9 22- 6 23- 2 23-10 24- 6 25- 2 25- 9
2x12 19.2 8-11 10- 3 11- 6 12- 7 13- 7 14- 6 15- 5 16- 3 17- 0 17- 9 18- 6 19- 3 19-11 20- 6 21- 2 21- 9 22- 5 23- 0 23- 6 24- 1 24- 8 25- 2
24.0 7-11 9- 2 10- 3 11- 3 12- 2 13- 0 13- 9 14- 6 15- 3 15-11 16- 7 17- 2 17- 9 18- 4 18-11 19- 6 20- 0 20- 6 21- 1 21- 7 22- 0 22- 6
E 12.0 0.14 0.22 0.31 0.41 0.51 0.63 0.75 0.88 1.01 1.15 1.30 1.45 1.61 1.77 1.94 2.12 2.30 2.48
E 16.0 0.12 0.19 0.27 0.35 0.44 0.54 0.65 0.76 0.88 1.00 1.12 1.26 1.39 1.54 1.68 1.83 1.99 2.15 2.31 2.48
E 19.2 0.11 0.18 0.24 0.32 0.41 0.50 0.59 0.69 0.80 0.91 1.03 1.15 1.27 1.40 1.54 1.67 1.81 1.96 2.11 2.26 2.42 2.58
E 24.0 0.10 0.16 0.22 0.29 0.36 0.44 0.53 0.62 0.71 0.81 0.92 1.03 1.14 1.25 1.37 1.50 1.62 1.75 1.89 2.02 2.16 2.30
Note: The required modulus of elasticity, E, in 1,000,000 pounds per square inch is shown at the bottom of each table, is limited to 2.6 million psi and less, and is applicable to all lumber sizes shown. Spans are shown in feet-inches and are limited to 26′ and less. Check sources of supply for availability of lumber in lengths greater than 20′.
TABLE R-10
RAFTERS WITH L/240 DEFLECTION LIMITATION
DESIGN CRITERIA
Strength - Live Load of 30 psf plus
