Bottom is 18" deep, top is 12". Definitely usable for putting on/taking off shoes in that function without doors in the way. The doors would hamper that significantly, I would avoid them and live with them looking like they are used. Expecting your kids to open doors and neatly put their stuff away probably isn't realistic anyway.
We have that bench area under the window which is nice to have and the storage underneath is very useful. If you want doors, trimming down to locker to leave a bench space at one end is a good idea.
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Tile transitions ideas
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