The lowest is a plain ceiling joist with no storage 10 pounds per square foot.
Floor joist load rating calculator.
Species southern pine douglas fir larch hem fir spruce pine fir redwood western cedars ponderosa pine red pine.
While every effort has been made to insure the accuracy of the information presented and special effort has been made to assure that the information reflects the state of the art neither the west coast lumber inspection bureau the american wood council nor its members assume any responsibility for any particular design prepared from this online span calculator.
This is how far apart they will be.
There are six choices.
Span calculator for wood joists and rafters also.
True floor joist span calculations can only be made by a structural engineer or contractor.
This sample table gives minimum floor joist sizes for joists spaced at 16 inches and 24 inches on center o c for 2 grade lumber with 10 pounds per square foot of dead load and 40 pounds of live load which is typical of normal residential construction.
Dead load weight of structure and fixed loads 10 lbs ft2.
Use span tables for progressively heavier loads until you find the limits of your floor.
Select the on center spacing for the joists.
Live load is weight of furniture wind snow and more.
Most lay outs are on 16 so the field is pre selected.
Span calculator for wood joists and rafters available for the iphone.
Span calculator for wood joists and rafters also available for the android os.
The highest is a fully loaded floor 70 pounds per square foot.
In this case your joists are adequate to support a 30 psf live load and 10 psf dead load.
Floor joist span use this table to determine the maximum lengths of floor joists based on species of lumber joist spacing and joist size.
2 grade of douglas fir are indicated below.
Live load psf dead load psf exterior exposure.
The span table for a 30 psf live load 10psf dead load floor indicates a required fb value of 1 315 and a minimum e value of 1 800 000.
For example a floor joist at 16 spacing s that can carry 53 pounds per linear foot would translate into a 318 pound single point load at its center.
Location and configuration of heavy loads should be looked at on a case by case basis.
Roof rafter span use this table to determine the maximum lengths of roof rafters based on species and grade of lumber spacing dimensions load and slope.
A uniform load rating on a beam can easily be translated into what an equivalent maximum point load can be.
1 psf lbf ft2 47 88 n m2.
