Maximum Floor Joist Span Calculator

Use the joist span and spacing calculator below to plug in your desired type of wood the size of your joists and the required spacing between each joist.

Maximum floor joist span calculator. Span calculator for wood joists and rafters also available for the android os. Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. Floor joist span calculator to use the joist span calculator below first select the species of lumber you will use for your construction project from the drop down list. Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters.

2 grade of douglas fir are indicated below. Dead load weight of structure and fixed loads 10 lbs ft 2. Floor joist span tables for surveyors floor construction surveyors and structural engineers use data from tables below to help calculate the size of timbers necessary to give adequate support to timber floors. This is how far apart they will be.

The highest is a fully loaded floor 70 pounds per square foot. Live load is weight of furniture wind snow and more. 1 ft 0 3048 m. Next use the buttons in the table to select the maximum length in feet or metres in brackets that your floor joists must span.

The lowest is a plain ceiling joist with no storage 10 pounds per square foot. 1 psf lb f ft 2 47 88 n m 2. Most lay outs are on 16 so the field is pre selected. Select the on center spacing for the joists.

Other span tables are based on the guidance given in bs 5268 7 1 which is a uniformly distributed load of 1 5kn m for spans greater than. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. Also available for the android os. The floor joist span tables are based on the loadings given in the amended version of bs 6399 1 which is an imposed load of either a uniformly distributed load of 1 5 kn m or a concentrated load of 1 4 kn.

Simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12. Maximum floor joist span for no. There are six choices.