How to Know Which Interior Walls Are Weight Bearing

Inspect the foundation by entering the basement or crawlspace. The foundation is typically made of cinder blocks outlining the perimeter of the house. Generally speaking, all walls standing on top of the foundation are load-bearing.

Identify the floor joists from the basement or crawl space. These are usually 2-by-10 feet boards that stretch across the foundation on their sides to support the bottom of the floor. Walls in the house that run parallel to the floor joists are usually not load-bearing, while walls that run perpendicular to them usually bear weight.

Look for any support beams in the basement or crawl space. In modern homes, these are usually metal poles that strut the joists from the ground. If you have a finished basement, these support beams are sometimes incorporated into structural walls. These walls will be wider than other walls to contain the poles. Any walls above these beams are probably load-bearing.

Access the attic and inspect the direction of the joists, which might be covered with insulation, if you can’t locate the joists from the basement. Interior walls that are parallel to these joists are generally not load-bearing.