Hi Ron,
NEDCC's preservation leaflet on Storage Furniture includes a section on this type of shelving, which gives an overview of the many factors necessary to consider when incorporating it into your storage space. Because the specifics will vary between situations, you'll need to research carefully to determine what will work for your collections and in your particular space. This includes consulting a structural engineer about the capacity of your floor, and working with vendors to learn what available options will be safe for your building.
A web search for "high density storage system," "compact shelving," or "moveable shelving" may be a good place to start learning about your options.
Please let me know if you have more questions.
Rebecca
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Rebecca Smyrl
Connecting to Collections Care Monitor
Assistant Conservator for Special Collections
UNC Chapel Hill Libraries
Chapel Hill NC
(919) 962-4250
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