Load-bearing walls keep buildings structurally sound, preventing sagging and potential collapse; in some cases, they may be moved or remodeled. Moving walls is a massive undertaking and potentially dangerous. Before you begin knocking out walls or even an area of a single wall, determine whether or not it's a load-bearing wall -- which takes more than looking at a floor plan.
Choose which wall or walls you want to move, remove or remodel based upon the home renovation project you have planned. You may physically identify these walls inside your home, or choose the project based on a diagram of the floor plan.
Consult with a professional structural engineer to discover if these walls are load bearing. The engineer may look at a diagram of your floor plan to become familiar with the overall layout and design of the house, but this does not help them determine which walls in your home are load-bearing as the floor plan does not contain detailed construction information.
Look above and below the walls if you have a basement or a second story. Load-bearing walls often are made with lapped joints in the joists and/or added braces or beams near the walls. The structural engineer will walk through your home to find these telltale signs to locate where the structural weight is being supported.
Support the framing in a load-bearing wall by adding a beam. Put this in place before proceeding with a project that changes the weight differential of a load-bearing wall.
Make structural changes to the home only after load-bearing areas have been identified by the professional and your plans for renovation have been checked and approved by the structural engineer.
Do not attempt to identify load-bearing walls using only a floor plan.