Little question, big answer...
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Without going into the details of exact dimensions, which of course make a big difference, we can say that the following characteristics have to be there, at the very least:
- there needs to be heat, and electricity
- natural light, and ventilation,
- a smoke (- and possibly a CO) detector,
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There are a few more requirements, like the size of the windows, spacing of the electrical outlets, a minimum of heat, but among all these criteria, believe it or not, a closet is not a must, although it is often considered such by real estate agents ... A good source of info is always your local building department.
Have more input on the matter, or a story to share? Feel free to chime in, I love stories...
Francis
useful links
PS: worthy cause: have you considered donating your extra fruits this season (if you have fruit bearing trees)?
contact: FullCircleSunnyvale.org