Roof Ceiling Joists

The roof joist is what makes up the ceiling of a home.

Roof ceiling joists.

They are nominally 2 inches thick actual width usually 1 1 2 inches and come in a variety of widths from 8 to 12 inches. They are spaced according to the material they support. The other surfaces are the walls which the joists span the distance between providing a source of support to keep the walls from shifting. If this is the case with your structure use the floor joist table to determine maximum joist length load.

Before we look at these tables we need to make sure the correct design loads are determined prior to selecting the correct table. Joists are the parallel horizontal beams that run across an open space joining opposite walls in a building to support both the ceiling below and the floor above. The joists are horizontal pieces of lumber that span the distance from one side of the home to the other. Typically the material is plasterboard which can span 450 mm.

Ceiling joists are normally horizontal members however under special circumstances they can be fixed on a slope. These span tables list allowable ceiling joist spans for common lumber sizes based on what design load scenario is applied. A broken roof joist is a serious problem that must be taken care of immediately. Joists are traditionally made from timber.

Ceiling joist spans for southern yellow pine douglas fir and eastern spruce. Standard size of joists. Ceiling joists of the first floor of a two story structure often serve as floor joists for the second floor. They are used to support a ceiling above or the floor below.

Ceiling joist loads ceiling joists are sized based on one of two tables found in the code. For coupled roofs ceiling joists have to be in single lengths or spliced.