Roof Joist Vs Truss

These triangulated structures with a high degree of strength and stability due to the geometry used form both the joist and rafter components of a building.

Roof joist vs truss.

Because they are manufactured off site according to the specifications of the project the need for alterations is almost completely eliminated. The simplest is a planar truss which is used as a roof support system. Trusses and rafters have many common parts including the sloping rafter boards and a bottom joists that form the ceiling of the space below. The joist also called bandsill supports the load which the floor is built to bear.

Floor trusses though are an economical alternative to joists. Both floor trusses and floor joist systems provide suitable structural support. This structural support comes in the form of roofing joists ceiling joists rafters or trusses and can be made from a variety of materials including wood metal reinforced concrete etc. However in canada the most common material used in residential framing is wood so that is the material we will discuss here.

Joists are used in floors and as column support. It is like the skeleton a building. The major functional difference between the two is that trusses are built mostly with 2x4s in place of the wider dimensional boards. As trusses are prefabricated they may be costlier than rafters however the installation and labor cost involved in roof rafters is comparatively higher than trusses.

Joists joists are supports that run between walls or beams to support the weight of floors roofs and ceilings. Trusses are of many types. While joists support the weight of floors and ceilings trusses have a wide variety of applications including supporting roofs and in bridge design. Roof framing has undergone a quiet revolution over the past half century.

Rafters could take an entire week to be installed whereas trusses could be installed in a day which means trusses could save a lot of time.