Most builders use plywood or OSB sheathing to laterally brace their framed walls and typically feel comfortable when they have a full sheet at both ends of the wall. I suspect that feeling is based more on intuition than on calculated strength, but most of the time it works. The plywood prevents the studs from racking and folding over, while nails through the bottom plate and hold-down straps prevent sliding and uplift from wind and earthquakes.
But what about walls with large openings and not much room for sheathing on each side? The most common example is the garage wall with, say, an 18-foot overhead door and two 16-inch walls at each side.
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