You need 2' for hanging space and 3' for walking. It's a waste of space to have a walk in without hanging on two sides, as you can actually get as much hanging space in less physical room with a reach in closet if you hang on only one side. So, you need at minimum 7' in width to do a efficient walk in with hanging on two sides. If you want an island in the middle with a bench for seating, then you need at least 12' of width. Length is dependent on amount of storage desired and space available.
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Great idea for empty wall maybe in guest BR ?
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