Hi Christina, and thanks for your questions. Caring for Archives: Fundamentals for Everyone from the C2CCare webinar archive is a good orientation to the many factors (including housing) to consider when dealing with unbound paper materials. For more detailed information about housing these materials, you could look at the Northeast Document Conservation Center's Preservation Leaflets.
The "Storage and Boxing for Unbound Documents" section of 4.1 Storage and Handling for Books and Artifacts on Paper gives an overview of the storage solutions I've seen most frequently used in paper-based archival collections. 4.4 Storage Enclosures for Books and Artifacts on Paper delves into the recommended criteria to use when evaluating housing materials available from vendors. And 4.9 Storage Solutions for Oversized Paper Artifacts discusses options for items too large to fit into standard letter- or legal-sized housings.
In general, folders (in turn housed in boxes or drawers) can often be a safer choice than envelopes for loose papers because they allow the papers to be accessed with less handling and abrasion than if they're being inserted and removed from an envelope. I'd also consider something heavier than tissue if interleaving is necessary. In many cases, a paper that's similar or slightly heavier in weight will support vulnerable paper better during handling as well as less likely to crease or crumple.
Thank you,
Rebecca
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Rebecca Smyrl
Connecting to Collections Care Monitor
Library & Archives Conservator
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