How to determine if a wall is load bearing

Answered by Brett Kulina ~ October 15, 2013 ~ No Comments

Are closets ever load-bearing?

I have an exterior closet in a house that was built in 1940 and want to tear it out. I am just concerned that it would be a load bearing structure.

-Amy

Brett Kulina

Amy, determining which walls in your home are "load bearing" is not always a straightforward task, and you should always seek the advice of an experienced carpenter or a structural engineer before removing or altering any walls in your home. The consequences of eliminating, or even weakening, a portion of your home's support structure can be expensive and dangerous.

To start, let's examine what a load bearing wall is and its function. As I'm sure you can guess, a load bearing wall is one that supports a significant weight (the load) above it and helps transfer that weight to the foundation of the house. For example, the four exterior walls of a hypothetical square house hold up the roof, which consists of heavy wood trusses, plywood sheathing, asphalt roof shingles, and (in some places) a couple feet of snow during a winter blizzard. The job of a load bearing exterior wall is to help support that weight and transfer the load to the concrete foundation footing, which sits on undisturbed or compacted earth.

On the other hand, a non-load bearing wall might be an interior wall that simply divides the bathroom from the kitchen, but is not supporting any significant weight from above. The problem is that many of us live in homes that were built long ago, and no blue prints exist to indicate which wall structures are load bearing and which ones are not. Compounding this problem is the fact that most home's wall framing is hidden behind sheet rock walls, which makes it difficult to determine the underlying framing and wall structure.

So although it may be tempting to classify all exterior walls as load bearing and all interior walls as not load bearing, that is definitely not the case. In fact, a typical exterior wall has both load bearing and non-load bearing points. For example, an exterior wall on the first floor of a house may support the load of the second floor and the roof, but that same wall also has openings for doors and windows, which can't support any significant weight. Those window and door openings are free from overhead loads because of a framing technique called "a header," which is a horizontal framing member that spreads a given load to two vertical framing members, leaving an opening for a glass window or some other wall opening. Some headers may be just a few feet long, such as a header above a window, but think about the load transfer involved in a header that sits above a 20-foot garage door opening!

In addition to headers, there are many other framing techniques that carry, transfer, or create loads that are not always apparent to the DIY homeowner who simply wants to remove a wall during a routine home remodel. That's why it's necessary to consult an experienced carpenter or structural engineer before you alter any walls in your house. By determing which walls in your home are load bearing, they can set you on the path to a safe and successful remodel.

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