Draw the shape of the moment diagram below.
Floor joist design example.
Calculate the moment due to dead load.
Calculate the dead load on a typical purlin.
Design a typical floor joist for the two story office building indicated below.
Design of 2x12 timber floor joist with douglas fir larch design of sawn timber beams or joists.
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.
The floor joist spacing is the distance between the centers of any two installed joists.
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.
See the image below for an example of joists spaced 16 on center 16 o c.
Design of 3 3x12 timber beam with southern pine solved example.
Drywall attached to the underside of this system is not expected to crack when the floor joist system deflects 1 3.
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.
Ce 331 spring 2002 joist and frame design example 1 2 1.