When joists trusses are perpendicular to the wall and bear on the top of the wall that wall is bearing wall.
How to tell load bearing wall with truss roof.
However there are cases where a bearing wall is parallel to the joists.
An example of a non load bearing partition wall can be seen on the left.
1 when the home has an l or t shape there may be an interior bearing wall under the intersection of the perpendicular rows of trusses.
But if the wall runs perpendicular at a 90 degree angle to the joists there is a good chance that it is load bearing.
Load bearing walls cross roof beams in a perpendicular direction.
We usually build on the exterior walls set the trusses and do all of the chord blocking and truss bracing before buildin.
Residentiall roof trusses are designed to bear only on the exterior walls at each end of the span.
One top plate and a space between the bottom chord of the truss and the top of the wall non load bearing.
For example a gable end truss may be designed with support members that transmit the roof weight load outward to the side walls allowing the end wall directly below it to have breaks or openings in it that would otherwise be impossible.
Actually a quick way to determine if the wall is bearing is to cut hole at the top to see if it has one or two top plates.
Chances are this is a non bearing wall.
But there are five possible exceptions to look out for.
Engineered roof truss systems may be designed to eliminate the need for load bearing walls or change where the bearing walls are located.
If the wall in question is parallel to the joists trusses it will likely not be load bearing.
If you see these nearby internal walls may not be load bearing.
Look for the signs of big sturdy wooden or metal structures crossing a room s ceiling and intersecting a wall that you know is load bearing or an external wall like boxy horizontal protrusions crossing the ceiling.
If a wall is located on the ground floor go down to the basement to observe the ceiling beams.
An example of a load bearing wall call be seen on the right.
Most simple construction truss roof home s roof and trusses are supported by the exterior walls perpendicular to the trusses.