Roof Truss Span Tables

The load span tables shown below demonstrate only a tiny subset of the possible combinations available with trussteel cfs roof trusses.

Roof truss span tables.

Straight line interpolation shall be permitted for intermediate spans and design values. The calculated spans assume fully supported members properly sheathed and nailed on the top edge of the joist or rafter. Keep in mind that these tables are for estimations only. Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters.

Typical roof truss design spans general notes. They have not been updated for the change in lumber values within the last decade. Joist and rafter span tables. Span tables use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads.

Roof floor truss manual 7 31 08 10 43 am page 12. And parallel to floor truss span strongback lateral supports 24 max. Span calculator for wood joists and rafters also available for the android os. The same thing is true for the bridge of the truss.

These span tables assume installation of at least three joists or rafters that are spaced not more than 24 on center. Roof truss span tables. View joist rafter tables. Also available for the android os.

Simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12. Top chord 2x4 2x6 2x6 2x4 2x6 2x6 2x4 2x6 2x6 2x4 2x6 2x6 bottom chord 2x4 2x4 2x6 2x4 2x4 2x6 2x4 2x4 2x6 2x4 2x4 2x6 2 12 24 24 33 27 27 37 31 31 43 33 33 46 2 5 12 29 29 39 33 33 45 37 38 52 39 40 55 3 12 34 34 46 37 39 53 40 44 60 43 46 64 3 5 12 39 39 53 41 44 61 44 50 65 47 52 70 4 12 41 43 59 43 49 64 46 56 69 49 57 74 5 12 44 52 67 46 58 69 49 66 74 53 66 80 6 12 46 60 69 47 67 71 51 74 76 55 74 82 7 12 47 67 70 48. 1 spans shown in charts are in feet. 72 5 0 mi ni m u m girder floor truss floor truss jacks a a bearing wall girder floor truss floor truss jacks bearing wall cantilevered floor truss two 2x rim joists 24 max.

Finally the truss calculator will compute the best dimensional method to connect the pieces of the truss with steel joints and a bridge. Every trussteel roof truss is a custom design based upon the unique load span bearing use and code criteria of a particular project. These steel joints are needed to support the overall truss. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths.