Hi Trisha,
If your oversized items can continue to be stored in the flat file, rather than constructing portfolios I would recommend ordering map or print folders for them. This could be a simpler option for you labor-wise and involves fewer materials (i.e. single pieces of folder stock as opposed to board, hinge material, and adhesive) that could interact with your collections. They're available in many sizes and can be cut down as needed. Depending on condition, it's generally safe to store multiple items in a single folder and/or to use sub-folders to protect more vulnerable items.
C2CCare can't recommend/endorse specific products, but an online search for map and print folders will give you some options. In general, products that are clearly specified as acid-free, lignin-free, buffered, and passing the Photographic Activity Test (PAT) should be safe for most paper materials.
Folders aside, you might still want a rigid option to support materials during handling and transit. This could just be a large board that folders could sit on, two large boards that folders could be sandwiched between if they are too large to fit through a doorway while sitting flat, or more elaborate options like the one I'm including in the links below.
Guidelines for oversize storage:
o Storage Techniques for Art, Science, and History 's Storage of Large Paper Objects
Criteria to look for when shopping for housing materials:
Portfolios:
Please let me know if you have follow-up questions,
Rebecca
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Rebecca Smyrl
Connecting to Collections Care Monitor
Library & Archives Conservator
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Original Message:
Sent: 09-24-2025 11:37
From: Trisha Shepard
Subject: Storing oversized paper materials
We have a small collection of oversized newspapers, poster sand ephemera that we currentlyhave in a flat file. Looking for recommendations on constructing some large (30 X 40") portfolios to be able to protect, organize and make safely accessible. Specifics on board and tissue choice and sources? Thanks for any guidance.
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Trisha Shepard
Operations Manager
The Powers Art Center
Woody Creek
United States
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