Floor Joist And Wall

In building constructions the term joist refers to a horizontal framing member that is the primary structural element of a floor or ceiling frame.

Floor joist and wall.

Both are horizontal members meaning they are installed level with the ground or floor below and both are supported on their ends and sometimes in their middles by load bearing walls columns or other types of vertical supports. How joists support floors and ceilings joists the horizontal members that span two walls and or beams have to carry the weight of the walls people furniture appliances and other stuff we place on them. True floor joist span calculations can only be made by a structural engineer or contractor. They are covered with subflooring panels of plywood or oriented strandboard osb to complete the floor s structural assembly and create the solid continuous platform on which you install tile carpet or other finish flooring.

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. Joists are spaced at regular intervals much like the studs in a wall frame. Normal spacing is 16 inches on center from center to center though some floors may have joists on 12 inch or 24 inch centers. When a load is applied to a joist the wood fibers along the bottom edge go into tension and those along the top go into compression fig.

Joists and beams are two types of structural elements that have similar and related functions in home construction.