40 Hour Property and Building Inspection Practice Test

What is the primary function of joists in a building structure?

1. To provide insulation

2. To transfer dead loads to foundations

3. To act as structural walls

4. To support roofing materials

The correct answer is: To transfer dead loads to foundations

The primary function of joists in a building structure is to transfer dead loads to the foundations. Joists are horizontal support members that span an open space and support flooring or ceiling materials. They are integral in distributing the weight of the various materials above them, such as flooring, and transferring that load down to the walls and ultimately the foundation. This load transfer ensures that the structural integrity of the building is maintained. While joists do indeed play a role in supporting roofing materials, as well as floors and ceilings, their main and most critical function is load transfer. Joists are not designed to provide insulation; that role is typically fulfilled by other components like insulation batts or rigid foam panels. Additionally, joists are not structural walls; walls serve different functions, including providing vertical support and separating spaces within the building. Thus, the focus on load transfer makes the identification of joists as primary load-bearing members essential in understanding their role in building structures.