When a home is built, the structure is composed of two types of walls. Load-bearing walls carry the weight of the structure and distribute the building's weight onto the building's foundation. Non-load-bearing walls are called partition walls and are built in place to divide rooms, create closets, etc. The building codes regarding how to construct the walls are different for each wall type.
A load-bearing wall carries the weight of the building and distributes that load onto the building's foundation. The load-bearing walls which are easiest to identify are the home's exterior walls. These walls carry the weight of the roof system. The roof trusses rest on these walls, and they create a continuous plane all the way down to the building's foundation. In most residential walls, a second set of load-bearing walls, one on each floor, exists along the centerline of the home. In the basement, this wall is created by a metal beam. Directly above the metal beam on first and second floors, a wall down the middle of the home also helps support the roof truss weight.
Framed Non-Load-Bearing Walls
A framed wall is any wall in the home that is not a load-bearing wall. Closets are a typical example of walls which are not load-bearing walls. Also called partition walls, framed walls create the internal rooms in a home. They can be moved, removed or shortened without affecting the building's structural integrity.
Load-Bearing Wall Remodeling
When a home is remodelled and changes are made to load-bearing walls, the weight of the building must be supported before, during and after the remodelling project. Before the project commences, the builder must insert temporary support which will carry the load during the project. Failure to do so can result in permanent damage to the home as the weight of the building shifts because it is not supported properly. If part of a load-bearing wall is removed as the result of the project, the wall's weight is supported by a header built into the opening. The header is a thick or built-up beam which will carry the home's weight without bending or buckling under the load.
Partition or Framed Wall Remodeling
Partition walls can be moved, torn out or installed in a remodelling project without consequence to the building's structural integrity. For example, unfinished basements are often finished off by adding walls, wall treatments, flooring and ceiling systems. These walls are attached to the load-bearing elements of the home, but they do not carry any of the weight of the home. Similarly, a project that involves tearing out framed, non-load-bearing walls between two bedrooms in order to create a single larger room can be completed easily. The walls can be removed without consideration to the structural integrity of the home.