Allowable Roof Spans – Canada

 

Simple Span – Table 8 – LDF = 1.15

Live Load = 20 psf  |  Dead Load = 15 psf  |  Snow Load = 1.15

Series  Depth Slope of 1/4:12 to 4:12 Slope of 4:12 to 8:12 Slope of 8:12 to 12:12
 16″ oc 19.2″ oc 24″ oc 16″ oc 19.2″ oc  19.2″ 16″ oc 19.2″ oc 24″ oc
PJI 40 9 1/2 21′-2″ 19′-11″ 15′-5″ 20′-4″ 19′-1″ 17′-8″ 19′-1″ 17′-11″ 16′-7″
11 7/8 25′-5″ 23′-10″ 21′-7″ 24′-4″ 22′-10″ 21′-0″ 22′-10″ 21′-6″ 19′-11″
14 28′-10″ 26′-6″ 23′-8″ 27′-8″ 25′-10″ 23′-1″ 26′-10″ 24′-5″ 22′-3″
16 31′-4″ 28′-7″ 25′-6″ 30′-6″ 27′-10″ 24′-10″ 28′-10″ 26′-10″ 23′-11″
PJI 60 9 1/2 22′-6″ 21′-1″ 19′-6″ 21′-7″ 20′-3″ 18′-9″ 20′-3″ 19′-0″ 17′-7″
11 7/8 27′-0″ 25′-4″ 23′-5″ 25′-10″ 24′-4″ 22′-6″ 24′-4″ 22′-10″ 21′-2″
14 30′-9″ 28′-10″ 26′-9″ 29′-6″ 27′-8″ 25′-8″ 27′-8″ 26′-0″ 24′-1″
16 34′-2″ 32′-1″ 29′-8″ 32′-9″ 30′-9″ 28′-6″ 30′-9″ 28′-11″ 26′-9″
PJI 80 11 7/8 30′-0″ 28′-2″ 26′-1″ 28′-10″ 27′-0″ 25′-0″ 27′-1″ 25′-5″ 23′-6″
14 34′-2″ 32′-1″ 29′-8″ 32′-9″ 30′-9″ 28′-6″ 30′-9″ 28′-11″ 26′-9″
16 37′-11″ 35′-7″ 32′-11″ 36′-4″ 34′-2″ 31′-7″ 34′-2″ 32′-1″ 29′-8″
18  41′-4″ 38′-10″ 35′-11″ 39′-7″ 37′-3″ 34′-6″ 37′-3″ 35′-0″ 32′-5″
20 44′-9″ 42′-0″ 38′-11″ 42′-11″ 40′-4″ 37′-4″ 40′-4″ 37′-10″ 35′-1″
22 48′-1″ 45′-1″ 41′-9″ 46′-1″ 43′-3″ 40′-1″ 43′-3″ 40′-8″ 37′-8″
24  51′-3″ 58′-2″ 43′-10″ 49′-2″ 46′-2″ 42′-8″ 46′-2″ 43′-5″ 40′-3″

 

Simple Span- Table 9 – LDF = 1.15

Live Load = 30 psf  |  Dead Load = 15 psf  |  Snow Load = 1.15

Series  Depth Slope of 1/4:12 to 4:12 Slope of 4:12 to 8:12 Slope of 8:12 to 12:12
 16″ oc 19.2″ oc 24″ oc 16″ oc 19.2″ oc  19.2″ 16″ oc 19.2″ oc 24″ oc
PJI 40 9 1/2 18′-5″ 17′-3″ 16′-0″  17′-8″  16′-7″ 15′-4″  16′-9″  15′-9″  14′-7″
11 7/8  22′-1″ 20′-9″ 18′-11″ 21′-2″  19′-11″ 18′-5″ 20′-1″ 18′-11″  17′-6″
14 25′-1″ 23′-3″  20′-9″  24′-1″  22′-7″  20′-4″ 22′-10″ 21′-5″ 19′-9″
16 27′-5″ 25′-0″ 22′-4″ 26′-9″  24′-6″  21′-11″ 25′-4″ 23′-10″ 21′-3″
PJI 60 9 1/2  19′-6″  18′-4″ 16′-11″ 18′-9″  17′-7″  16′-3″  17′-10″ 16′-9″  15′-6″
11 7/8  23′-5″ 22′-0″  20′-4″  22′-6″ 21′-11″ 19′-6″ 21′-4″  20′-1″  18′-7″
14 26′-9″ 25′-1″ 23′-2″  25′-8″  24′-1″ 22′-3″  24′-4″ 22′-10″ 21′-2″
16 29′-8″ 27′-11″ 25′-9″ 28′-6″ 26′-9″ 24′-9″  27′-1″ 25′-5″ 23′-6″
PJI 80 11 7/8 26′-1″ 24′-5″ 22′-7″ 25′-0″ 23′-6″ 21′-9″  23′-9″  22′-4″ 20′-8″
14  29′-8″ 27′-10″ 25′-9″ 28′-6″  26′-9″ 24′-9″ 27′-1″ 25′-5″  23′-6″
16 32′-11″  30′-11″ 28′-7″  31′-7″ 29′-8″ 27′-5″ 30′-0″ 28′-2″  26′-1″
18  35′-11″ 33′-8″ 31′-2″  34′-6″ 32′-4″ 29′-11″  32′-9″ 30′-9″ 28′-6″
20  38′-11″ 36′-6″ 33′-9″ 37′-4″ 35′-1″ 32′-5″  35′-5″ 33′-4″  30′-10″
22 41′-9″  39′-3″ 36′-3″  40′-1″  37′-8″ 34′-10″  38′-1″ 35′-9″ 33′-1″
24  44′-7″ 41′-10″ 38′-5″ 42′-9″  40′-2″ 37′-2″ 40′-8″  38′-2″  35′-4″

 

Simple Span – Table 10 – LDF = 1.15

Live Load = 40 psf  |  Dead Load = 15 psf  |  Snow Load = 1.15

Series  Depth Slope of 1/4:12 to 4:12 Slope of 4:12 to 8:12 Slope of 8:12 to 12:12
 16″ oc 19.2″ oc 24″ oc 16″ oc 19.2″ oc  19.2″ 16″ oc 19.2″ oc 24″ oc
PJI 40 9 1/2 16′-8″  15′-7″ 14′-5″ 16′-0″  15′-0″  13′-10″ 15′-2″ 14′-3″  13′-2″
11 7/8  20′-0″ 18′-9″ 17′-0″ 19′-2″ 18′-0″  16′-8″ 18′-2″  17′-1″  15′-10″
14  22′-8″  20′-11″  18′-8″  21′-9″  20′-5″  18′-4″ 20′-8″  19′-5″ 17′-11″
16 24′-8″ 22′-6″  20′-2″ 24′-2″ 22′-2″ 19′-9″  23′-0″ 21′-7″  19′-4″
PJI 60 9 1/2 17′-8″ 16′-7″  15′-4″ 17′-0″  15′-11″ 14′-8″ 16′-1″  15′-1″ 14′-0″
11 7/8  21′-2″ 19′-11″ 18′-4″ 20′-4″  19′-1″  17′-8″  19′-4″ 18′-2″  16′-10″
14  24′-2″  22′-8″ 20′-11″ 23′-2″  21′-9″ 20′-1″ 22′-1″ 20′-8″ 19′-2″
16  26′-10″  25′-22″ 23′-4″ 25′-10″ 24′-3″ 22′-5″  24′-6″  23′-0″ 21′-4″
PJI 80 11 7/8  23′-7″  22′-1″ 20′-5″  22′-8″  21′-3″ 19′-8″  21′-6″ 20′-2″  18′-8″
14 26′-10″ 25′-2″  23′-3″ 25′-9″ 24′-2″  22′-4″ 24′-6″  23′-0″ 21′-3″
16 29′-9″ 27′-11″  25′-2″  28′-7″ 26′-10″ 24′-3″  27′-2″  25′-6″ 23′-2″
18 32′-6″ 30′-6″  28′-2″  31′-2″  29′-3″  27′-1″ 29′-8″ 27′-10″ 25′-9″
20 35′-2″ 33′-0″  30′-6″ 33′-9″  31′-9″ 29′-4″ 32′-1″  30′-2″  27′-11″
22  37′-10″ 35′-6″ 32′-9″  36′-4″ 34′-1″ 31′-6″  34′-6″ 32′-5″  30′-0″
24  40′-4″  37′-10″  34′-7″ 38′-9″  36′-4″ 33′-8″ 36′-10″ 34′-7″ 32′-0″

 

Simple Span – Table 11 – LDF = 1.15

Live Load = 50 psf  |  Dead Load = 15 psf  |  Snow Load = 1.15

Series  Depth Slope of 1/4:12 to 4:12 Slope of 4:12 to 8:12 Slope of 8:12 to 12:12
 16″ oc 19.2″ oc 24″ oc 16″ oc 19.2″ oc  19.2″ 16″ oc 19.2″ oc 24″ oc
PJI 40 9 1/2  15′-5″ 14′-5″  13′-4″  14′-9″ 13′-10″ 12′-10″ 14′-1″ 13′-2″  12′-2″
11 7/8  18′-5″ 17′-4″  15′-7″  17′-9″  16′-8″ 15′-4″ 16′-10″ 15′-10″  14′-7″
14  21′-0″  19′-2″ 17′-2″ 20′-2″ 18′-11″  16′-11″ 19′-2″ 18′-0″ 16′-6″
16  22′-8″ 20′-8″ 18′-5″ 22′-4″  20′-4″ 18′-2″  21′-3″ 19′-11″ 17′-10″
PJI 60 9 1/2  16′-4″ 15′-4″ 14′-1″ 15′-8″  14′-8″ 13′-7″ 14′-11″ 14′-0″ 12′-11″
11 7/8  19′-7″  18′-4″  16′-11″  18′-10″  17′-8″  16′-4″ 17′-11″ 16′-10″  15′-6″
14  22′-4″ 20′-11″  19′-4″  21′-6″  20′-2″  18′-7″  20′-5″  19′-2″  17′-9″
16  24′-10″  23′-4″  19′-10″  23′-10″  22′-5″  19′-3″  22′-8″  21′-4″  18′-6″
PJI 80 11 7/8  21′-9″  20′-5″  18′-10″  20′-11″  19′-8″ 18′-2″  19′-11″ 18′-8″ 17′-3″
14  24′-10″  23′-3″ 21′-2″ 23′-10″  22′-4″  20′-6″  22′-8″  21′-3″  19′-8″
16 27′-6″  25′-10″ 21′-2″ 26′-5″ 24′-10″  20′-6″  25′-2″ 23′-7″ 19′-9″
18 30′-0″ 28′-2″ 26′-0″  28′-10″ 27′-1″ 25′-0″ 27′-5″  25′-9″  23′-10″
20  32′-6″ 30′-6″ 28′-2″  31′-3″  29′-4″  27′-1″ 29′-9″ 27′-11″  25′-10″
22  35′-0″  32′-9″  30′-3″  33′-7″ 31′-6″  29′-2″ 31′-11″ 30′-0″ 27′-9″
24  37′-4″  35′-0″  31′-8″ 35′-10″  33′-8″  31′-1″  34′-11″  32′-0″ 29′-7″

 

NOTES:

  1. Design is to CSA O86S1-05.
  2. Spans are for joists supported at each end only (ie no intermediate supports). For other conditions contact the manufacturer.
  3. Spans listed are clear distances between supports.
  4. Web stiffeners are not required for joist depths up to 16”. Depths of 18” or greater require web stiffeners at each support.
  5. Use in dry service conditions only.
  6. Provide continuous lateral support for top flange. Provide lateral support at points of bearing to prevent twisting of the joist.
  7. Uniform load deflection criteria is L/360 on live load and L/180 on total load.Deflection calculated using joist properties only
  8. Provide a roof slope of at least 1/4 in 12 for drainage.
  9. Provide 1-3/4” horizontal bearing at each support, minimum.
  10. Sloping joists need to be anchored to each support to resist a sliding force of:
    Hf = (0.5 wf L y) / (y2+144)1/2
    where Hf = factored force parallel to the joist (lb), wf = factored horizontally projected loading (plf),
    L = horizontal span (ft), y = roof slope: rise in 12