Floor Joist Design Example

Calculate the moment due to dead load.

Floor joist design example.

Drywall attached to the underside of this system is not expected to crack when the floor joist system deflects 1 3. Calculate the dead load on a typical purlin. The extra two inches of vertical distance when a floor is framed with 2 x 10 joists rather than 2 x 12s can be quite important for example. A floor joist appropriately selected to span 10 feet with an l 360 limit will deflect no more than 120 360 1 3 inches under maximum design loads.

Common sense tells you that large floor joists can carry more load and spacing joists closer together also increases the load bearing capacity of a floor. Ce 331 spring 2002 joist and frame design example 1 2 1. Draw the purlin and show the dead loading. Draw the shape of the moment diagram below.

Design of 3 3x12 timber beam with southern pine solved example. See the image below for an example of joists spaced 16 on center 16 o c. But larger is not always better when builders are constructing a home or adding a room addition. Design of 2x12 timber floor joist with douglas fir larch design of sawn timber beams or joists.