BPG Housings

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Book and Paper Group Wiki > Housings

Housings are protective enclosures for objects intended to mitigate deterioration from physical and chemical factors in the environment. Housings for paper objects vary in design and materials depending on an object’s format, how it will be used, and how it will be stored. Standard housings for book and paper materials are outlined here as well as factors to consider in planning housing projects. For housings for photographic materials, see PMG Preservation Housing Materials and Formats.

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Wiki Compilers: Jessica Makin, Jo Anne Martinez-Kilgore, Susan Russick
Wiki Contributors: Angela M. Andres, Melina Avery, Sonya Barron, Mary Baughman, Lou Di Gennaro, Stephanie Gowler, Cynthia Kapteyn, Katherine Kelly, Susannah Kendall, Evan Knight, Andrea Knowlton, Ann Lindsey, Suzy Morgan, Sarah Reidell, Nicole Royal, Michelle C. Smith, please add your name

Copyright 2024. The AIC Wiki is a publication of the American Institute for Conservation (AIC). It is published as a convenience for the members of AIC. Publication does not endorse nor recommend any treatments, methods, or techniques described herein. Information on researching with and citing the wiki can be found on the Reference and Bibliography Protocols page.

Cite this page:

American Institute for Conservation (AIC). "BPG Housings." AIC Wiki. December 22, 2024. https://www.conservation-wiki.com/wiki/BPG_Housings.

General Considerations

Protection of the Object During In-House Storage

Physical

Housing design should protect and support an item and be absent of features that will cause any damage over time. The design should also be “user friendly” - intuitive to open and close, if possible. A housing structure should be capable of being opened easily and staying closed when at rest. The components of the housing that are in contact with the item should not have any edges that could mark the item over time and should fit the item well so that no shifting occurs within the housing. Housings should not be overly heavy or cumbersome to move. This issue becomes a significant design concern when housing large and heavy objects. Closures should be easy to use and should remain attached through many uses.

Chemical

ISO standards for paper, paperboard, and plastic to house cultural heritage materials are numerous. These standards measure the physical and chemical characteristics of materials and work to ensure that products are permanent and durable over time.

Materials that are slower to degrade and are less reactive with other substances should be used for housings. In general, long lasting paper and paperboards are those that are free of lignin, pH neutral or alkaline buffered, composed of high-quality raw materials such as long cellulose fibers, and free from harmful additives (coatings, release agents, etc.). Stable plastics such as polyester terephthalate (Mylar™, Melinex™), polyethylene (Ethafoam™, Tyvek™), and polypropylene are chemically acceptable. Even chemically acceptable materials may present other issues such as static electricity.

It is good to gather information on all products purchased for preservation of collections. When identifying products to purchase, watch for language from vendors citing standards and the PAT (photographic activity test). Ask to view Material Data Sheets and watch for language citing the use of additives, fillers, or coatings. Ask for samples of products before purchase. If possible, talk with colleagues concerning vendors or products that are known to be consistently preservation quality and of high-quality manufacture.

Prioritization and Selection for Housing

See also: Selection for Preservation

Deciding how to prioritize housings can involve several groups of considerations. Qualities that may influence the decision include the needs of the object, how the object will be used, where it will be stored, and how it will be marked or identified.

Objects which may be prioritized for housings include irregularly shaped or multipart objects. For these, the housing can allow non-standard objects to sit on the shelf, keep all pieces or sets of materials together and in order, and can make it obvious if a part is missing. Fragile or reactive materials may benefit from a housing by providing physical protection, mitigate fluctuations in temperature and humidity, and aid in chemical stability. Housing of an object may be prioritized if the object is damaging to adjacent materials, such as being scratched by the neighboring book’s clasps. Housings can be used to protect people in cases where materials are hazardous because they were created using toxic components, have been exposed to mold, or were poisoned as a pest control measure.

The location where the object will be stored can influence the type of housing. Furniture can dictate standard sizes for folders and boxes. Some locations, such as high-density storage facilities may require special features such as handles on boxes or barcodes.

Housings can ease handling and object use. An object that is very low use can be housed prioritizing density, while frequently used materials may be stored in housings that can double as display mounts. Housing for circulating materials may need to provide sturdy, foolproof protection.

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  This two-sided letter is matted with a digital image of the reverse

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  It can be opened wide to stand for a show-and-tell or closed like a folder for storage

• Images courtesy of Northwestern University

Cost

Cost can be a significant factor in choosing housing solutions. This issue should be considered relative to the materials required, but also in the amount of staff time it takes to complete a housing project, and the amount of space the housings will occupy in storage. The most cost-effective approach for housing is usually to standardize solutions within the collection but have the flexibility to customize when considerations dictate. Standard solutions allow objects to be grouped within drawers, boxes and on shelves. Individual objects may require an investment in custom solutions because of their structure or how they will be used. The cost of materials, necessary staff time, the space available for housings in storage (including the added bulk of the materials used to create them) should be considered in the planning process. In projects with large numbers of housings, these dimensions can add up.

For example, housing individual objects in multi-layered matting structures within drawers occupies a significant amount of space but provides a stable way to access and display frequently used materials. Matting in storage may be appropriate for art on paper. Storing groups of objects in folders and boxes provides high density storage that is not dependent on flat file drawers, which are often the most costly storage option. High density storage is often used in archives. A four-flap book box made of 20 pt. board will add a few millimeters of shelf space while a box made of 60 pt. board will triple that. Libraries often will house smaller and lighter weight volumes in boxes made of thinner materials to save shelf space when possible.

Protection of the User

See also: Mold

Housings can protect the user from the object, whether the object is hazardous due to its original materials, use, or exposure to biohazards such as mold. Labeling on the housing indicating the hazard(s) present is warranted.

Historically, many materials used for record production have included hazardous chemicals. Common examples of these include numerous pigments and some metals. Lead based pigments (white and red) have been used as media on the page. Brown lead pigments have been used to coat end leaves of books as a pest control measure. Lead can also be used in tax stamps and seals. Vermillion or cinnabar, which are mercury based, were commonly used for rubricating manuscripts and are an ingredient in red wax seals. Orpiment (yellow) contains arsenic. Emerald green (copper acetoarsenite) has been used for book cloth (Tedone 2020).

Materials can become hazardous due to original use, such as Marie Currie’s notebooks being radioactive. These papers are stored in lead-lined boxes at the Biblioteque National in Paris (Tasch 2015).

Most commonly, materials have been exposed to mold, pesticides, animal waste or other biohazards. While still of value, they may carry toxins or likely allergens that are unsafe to store without a housing. Mold can result in visible fungal bloom, blocking of papers, odors, and severe allergens. Pests can leave casings, carcasses, excrement, and nesting materials behind. These can hold bacteria and viruses including the rodent transferred Hantavirus. In order to deter pests, a wide variety of chemicals have been historically used. Pesticides can be difficult to identify. DDT and other pesticides may appear as a white or tan powder sprinkled onto scattered pages, gray crystals, or as staining from a liquid spray. Often there is no visible presence, but an odor that alerts the conservator that a pesticide is present. Personal protective equipment is recommended when handling materials exposed to mold, pests and pesticides.

Housings can isolate materials to limit spread of hazardous materials during storage. Labels can warn users before opening the box.

Accessibility

Accessibility is an important factor in the choice of an effective housing. Consider the ways that an object might be used within the collection. Ask if it will be displayed, is it part of a circulating collection, or will it need to travel? Is there a housing that might protect and support an object during storage and use while still fitting into standards dictated by similar objects or limitations on storage space?

Objects that are often used for study may need to be protected from frequent handling. An encapsulation or a “back and wrap” housing would protect an object from the oils that may be deposited from a person’s hands and offer physical support. Objects that are often displayed may need to be fitted into a case or a frame so a housing which can be flexible for storage and display may be ideal. A storage mat or cloth covered box might be appropriate and prevent the need to move the object to a new housing for display. If an object is accessed often, it might be stored in an individual folder in a drawer rather than rolled with other objects around a tube, reducing the need to disturb other objects.

Presentation

After considering how the object will be used within the collection, the level of presentation or “fancy factor” will also have bearing on the housing design. Will the object be displayed in its housing? This issue will inform how elaborate or finished a housing should look and the expense (in time and materials) required. Its presentation can affect the perception of its relative importance or value. Examples include a flat paper object housed in a mat that can be used for storage and framed display or a beautifully constructed cloth covered custom box may hold an object for study, storage, and exhibition. Housings may help maintain order and add security.

Labeling

Identification of collection materials is crucial to maintaining item control of objects. Groups of materials or individual items are assigned identification names or numbers during the cataloguing or archival description process. Additional information such as barcodes, item numbering, etc. may also be required. The type of collection may dictate if the information is applied to the object itself versus the housing.

Object Marking

• Direct Marking of Objects - Collection materials may be marked directly on the object with hand applied inscriptions, ink transfer stamps, book plates, labels or through other methods. The manner of marking should be consistent and done using long lasting materials. While the marking should not disfigure the object, some institutions intentionally mark materials in a readily visible place as a theft deterrent. The practice of directly marking objects varies - most libraries directly mark circulating collections and may apply some direct marks to special collections materials.
• Indirect Marking of Objects - For some materials, indirect marking is preferred. Individual materials are indirectly marked using book flags, tie-on tags, non-adhesive plastic straps are applied to the object. Indirect markings are often used for museums, archives, and special library collections and to augment and expand on direct identification.

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• Images courtesy of Northwestern University

Labeling of Housings

Identification of materials by marking housings is often used for archival materials. Individual objects in archives may not be marked directly on the objects themselves.

The accurate and comprehensive labelling of housings is crucial to reduce the handling and wear and tear on the housing and the object contained. The text of any label should be as brief as possible while adequately describing the contents. At minimum labels should contain a unique identifying number.

Labelling can be printed on paper or other substrate (laser or inkjet), handwritten, embossed or inked by a machine, or hot stamped on leather or paper. Labels can be adhered with liquid adhesive, pressure sensitive adhesive, or can be precoated with water activated or heat activated adhesive.

Attention to using legible font and a font size that is large enough to be readily visible is important. Photographs may be included on labels to aide in object identification and reduce handling. Paper and inks used for labelling should be durable and permanent. It may be advisable to coat computer printed labels to “fix” inks onto paper. If possible, test label materials (paper and adhesive) to observe how they resist to abrasion, fading, and adhesive failure.

Another important aspect of labelling is to indicate if the contents are fragile, hazardous, restricted or emotionally impactful (crime scene photos). Appropriate wording reflecting institution policy should be consistent and clear.

Storage Environment

See also: Environmental Guidelines and Ten Agents of Deterioration

Maintaining appropriate temperature, relative humidity, freedom from pollutants, light and other conditions for collection materials is critical. Housings can mitigate imperfections in the storage environment or can exacerbate problems.

Housings produce microenvironments which may have positive or negative results. A housing may smooth sudden shifts in temperature and humidity, block light and reduce gaseous and particulate pollutants.

The housing can be constructed using special materials to further alter the interior microclimate. Silica gel can be used to stabilize humidity, tarnish inhibitors can slow metal reactions, and zeolites can be used to absorb volatile organic compounds. These may require regular maintenance - if not changed periodically, the same chemical sponge used to absorb organic compounds can release them.

While plastic housings may protect objects during use, when they are used in high humidity environments, they can result in a microenvironment that can cause ferrotyping or encourage mold growth within the enclosure. Some plastic materials carry a static electric charge and can attract dust – they should be avoided in dusty environments. Corrugated structures can act as apartment buildings for nesting insects. Furniture may influence or dictate the type or size of housings used.

Case Studies

Russick, Susan. 2021."Common Housings for Paper Materials"

The following case studies outline the many variables considered while planning housing projects for paper-based materials and may act as helpful guides in decision making for similar materials or circumstances.

• Martinez-Kilgore, Jo Anne. 2021. “Housing Decision Making Case Study: Large Format Corrugated Clamshell Boxes for Aerial Photos.” Arizona State Library, Archives, and Public Records.

• Russick, Susan. 2021. “Common Housings for Paper Materials.” Northwestern University Libraries.

• Russick, Susan. 2021. “Housing Decision Making Case Study: Lincoln Letter.” Northwestern University Libraries.

Flat Paper Housings

See also: PMG Preservation Housing Materials and Formats

So many types of housings exist that an exhaustive list is not possible. Standard housings are listed first and then some variations and customizations. This list focuses exclusively on flat paper objects.

Folders

There is a variety of folders that are commercially available or that can be custom made. Ideally, the quantity of objects in a given folder should be limited to a number the weight of which is well supported by the rigidity of the folder.

• Vertical – Vertical folders (or archival file folders) are often chosen for large collections of documents in good condition. They are stored in vertical document boxes, which can be a good space saving strategy. They can be purchased in bulk and made from various thicknesses of folder stock. They may be inappropriate for objects with vulnerable surfaces or for brittle paper.
• Flat – Flat folders can be used to store collections of documents or art on paper in good condition and without delicate surfaces. They can be stored in flat boxes or drawers. Flat folders can be made of various thicknesses of preservation quality folder stock and backings such as matboard or archival corrugated board may be added for rigidity and to support larger objects.
• Variations
  • Paper folder – A plain paper folder may be used within a standard 20 pt. folder as an alternative to a paper clip or a staple or to isolate a sticky object.
  • Padded folder – May be used to house a small 3-D items with flat paper materials.

Polyester film enclosures

See also: Encapsulation

Polyester film enclosures sandwich an object and offer protection in storage and for handling. Polyester enclosures can be sealed in a few ways, each with its own benefits and drawbacks. Seals attaching the two faces of polyester together are created with double-sided tape, heat, or an ultrasonic welder. Polyester film enclosures are often kept in folders within drawers or boxes but also in binders. Polyester film can be inappropriate for brittle objects or friable media because of the potential for static charge.

• Encapsulations are sealed on all four sides and provide the most protection but also the least access. The lack of air circulation has created a concern about the off gassing from an object to stay within the enclosure and contribute to degradation. The use of microchamber interleaving as a pollutant trap within an encapsulation can be helpful for some single-sided objects.
• L-sleeves are sealed on an adjacent short and long side while the opposite adjacent short and long sides are left open. Objects have some protection but can be removed from the sleeve easily.
• Three-sided pocket type enclosures are available and are often used within binders (see below). These offer good protection, but the insertion and removal of objects can be difficult.
• Folders
• Spot welding can be a useful technique for keeping irregular objects in place within a larger enclosure.

Custom Mylar Tray with Insert

This design for a custom Mylar tray with an insert can be used for housing an object with distinctive parts that need separation - designed by Nicole Royal and featured on the University of Virginia Library blog here: "Disparate objects UNITE! Preservation Housing Adventures in Mylar"

Back and wrap

A “back and wrap” housing is a technique where a paper object is backed with a rigid material, such as acid free matboard, and covered with a clear polyester film top sheet. The top sheet is cut large enough to allow it to be wrapped around and attached to the verso of the backing board with double-sided tape. The object has some protection from handling and can be temporarily displayed. Always use polyester film with caution because of the static charge.

Mats

See also: Matting and Framing

Paper objects can be matted for a flexible storage and display housing option. Acid free window mats and solid backings can be hinged together with gummed linen tape like a book. The paper objects may be attached to the interior of the mat package with hinges, paper corners, edge strips, or within a polyester enclosure. The mats can be stored in drawers or flat boxes and will also offer protection from handling. Mats are thicker than folders so can take up significantly more storage space.

Boxes

Two- part drop front storage boxes can be ordered from several suppliers or created from acid free multiuse corrugated board. These can be effective for storing rolled objects or large folders on shelving. They offer a layer of buffering from environmental agents of deterioration and support objects during handling.

• Gise, Chloe.“Drop down fold together box instructions.” Harry Ransom Center, University of Texas, Austin. 2020.
• Gise, Chloe.“ Drop-down box w-lid instructions.” Harry Ransom Center, University of Texas, Austin. 2020.
• Gise, Chloe.“ Fold-together box instructions.” Harry Ransom Center, University of Texas, Austin. 2020.

Oversized and Irregular

See Also: Housing of Oversized Prints and Drawings

Oversize paper objects may be stored in a variety of ways depending on their condition, use, and the availability of storage space.

Rolled storage

Oversize objects may be rolled on tubes that are stored inside boxes, which can be placed on shelving or storage racks. The face of the object should be protected by acid free interleaving or polyester film. The object is then rolled around the outside of an acid free tube. The larger the rolling tube diameter, the less stress on the object, but larger tubes require more storage space. The roll may be secured with a protective wrapper made from polyester film or acid free folder stock and secured with cotton twill ties or a similar gentle but secure method. This can be a space saving strategy for large objects, but they must be in good condition and not have vulnerable surfaces.

Futomaki for storage of scrolls and wall maps with rolling bars:

• Common uses: Scrolls and wall maps with rolling bars can not be rolled on plain cylindrical rolling tubes, but often the rolling bars that are part of these objects have such a small circumference that the paper and/or textile is physically stressed. Futomaki are a housing used for materials that have small diameter rolling bars built onto the object and would benefit from having a larger rolling tube.
• Typical materials: Traditional futomaki are made of wood, however they can be made of a variety of foams, papers and plastics.
• Possible concerns: Acids found in wooden futomaki may damage the scroll.
• Instructions:
  • STASH – Storage Techniques for Art, Science and History
  • "Mylar Preservation Rollers for Storing East Asian Scrolls" by East Asian Paintings Conservation Studio, Freer Gallery of Art and Arthur M. Sackler Gallery, Department of Conservation and Scientific Research, Smithsonian Institution
  • "Making Ethafoam Preservation Rollers for Storing East Asian Scrolls" by East Asian Paintings Conservation Studio, Freer Gallery of Art and Arthur M. Sackler Gallery, Department of Conservation and Scientific Research, Smithsonian Institution
  • "Making East Asian Scroll Storage Boxes" by East Asian Paintings Conservation Studio, Freer Gallery of Art and Arthur M. Sackler Gallery, Department of Conservation and Scientific Research, Smithsonian Institution
  • National Museum of Asian Art Storage Box Instructions
  • Northwestern University Libraries blog. “On a Roll: Creating a Futomaki-style housing for a large map." by Roger Williams

Oversize flat storage

• Folders - Large folders can be created from folder stock or constructed by hinging together sheets of matboard or acid free corrugated board, using book cloth and pH neutral polyvinyl acetate adhesive (PVA). Thicker materials can provide rigid support for a large object but will take up more storage space. Two people are often needed for handling large folders. These folders can be stored in drawers, on shelves, or in large boxes.
• Kapteyn, Cynthia and Sonya Barron. 2018. "A Table to Reckon With: Developing a Portfolio Housing Structure for an Oversized Periodic Table."

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  hinging

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  hinging

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  Portfolio open for display

• Andres, Angela. 2021. "Enclosure for galley proofs" - Galley proofs are challenging to house due to their long, narrow shape and shallow depth. This housing combines e-flute and 20-point boards in a slim, simple, and quick-to-make structure that is closed with cloth ties on the fore- edge and is easily stackable on the shelf.

Page protectors or photo album sleeves

Common uses: Materials that are visually interesting and are single leaves of paper such as postcards, ticket stubs, and flyers may be placed in commercially produced plastic sleeves or encapsulated in polyester film and may be put in a 3-ring binder box to maintain order. If single sided, a sheet of alkaline paper may be inserted behind the object to provide a better microclimate or can be used as a mount for non-standard sizes.

Typical materials: Polyethylene and polypropylene plastic sleeves are commercially available. Some older sleeves were made of polyvinylchloride, an unstable plastic, and should be removed.

Possible concerns: Microclimates in plastic.

Book and Pamphlet Housings

Determining the appropriate housing often depends on the dimensions of the book or pamphlet and so these are discussed generally in order from narrow and lightweight pamphlets to regular sized books, to oversize volumes, with some additional housing options listed at the end. Terminology varies between institutions and countries, so images and verbal descriptions are included. 

Envelope and Sling

Commonly used for small, irregular materials such as greeting cards, pamphlets of different sizes or postcards. Effective for materials with small loose parts. Often used in combination with a box.

Paper envelopes hold interior slings that protect the object from abrasion while sliding it into and removing it from the envelope.

Paper envelopes may not provide adequate structural rigidity to protect objects that are brittle or should not be flexed. They don’t always sit on the shelf well and it is awkward to browse through materials housed this way. 

Binders

Pamphlet binders

See also: Circulating Collections § Shelf Preparation

Common uses: Appropriate only for single section pamphlets up to about 1 cm width. These are available commercially in a variety of sizes and can be made in-house.

Typical materials: Attachment to the binder by sewing is considered reversible, whereas attachment using an adhesive method can present future conservation issues. Attachment with metal staples is an option, however staples can rust.

May be commercially available with a clear plastic front cover, however that option may be less environmentally sustainable than board covers.

Possible concerns: May not be appropriate for brittle materials or objects of artifactual value due to possible damage during sewing – most commonly used for circulating collections

Binder with Interior pocket or envelope – many varieties exist

Common uses: Appropriate for materials with a spine width of under about 5 mm, depending on manufacture

• Interior pocket can have an opening at the top (vertical orientation) or spine side (horizontal orientation)

• Often used with an interior sling or folder

Typical materials: Binders are typically made of 60 pt. board and cloth. Pockets may be made of paper, 10 or 20 pt. board, textile, or Tyvek.

Possible considerations: Binders with pockets may be a preferred housing for materials with irregular edges such as a pamphlet with a paper cover that is larger than the textblock. The cover’s edges could be crushed if housed vertically in a box, but the pocket may provide some support by cushioning the edges. Pockets with a vertical orientation may be more awkward to handle for larger materials and so are more appropriate for smaller objects.

Binder with Interior 4-flap

Common uses: Appropriate for materials with a spine width of under ~2 cm, depending on manufacture. These are commercially available or may be made in-house. Binders with pre-fabricated interior 4-flaps may be retrofitted.

Typical materials: Binders are typically made of 60 pt. board and cloth. Interior 4-flaps are often made of 10 or 20 pt. board. 4-flaps may be attached with double stick tape or an adhesive such as pH neutral polyvinyl acetate (PVAc). Some may have a Velcro closure.

Variations: Retrofitting

Book Shoe

Common uses: This box style is open at the head and spine of the book. It may be used for a single volume or for a group of narrow materials. These were developed as an aesthetically appealing housing that could invisibly hold books with detached boards on a shelf in a situation like permanent display in a historic home.

Typical materials:

Possible considerations:

Gise, Chloe. 2020. "Book Shoe Instructions." Harry Ransom Center, The University of Texas at Austin.

Slip Case

Most styles of slip case cover a book on 5 sides, leaving the spine exposed. The term slip case may also be used for a two-part box that holds the lower/tail half of the book and the upper/head half of the book. They are custom made for an individual book or for a set of books and are often issued by the publisher.

Slip cases are typically made from a paper-based board and covered with paper, cloth or leather, which has been adhered overall.

It can be difficult to get the book in and out of a slip case enclosure. The surface of the book covers may become abraded. The book spine can become damaged through exposure to light, temperature and humidity fluctuations and pollutants as well as handling. A polyester film or polypropylene dust jacket may be paired with the slipcase to protect the spine of the binding. While slip cases are not always considered a conservation housing, they have been historically used and do provide some protection to the text block.

4-Flap Box, Phase Box, or Portfolio Box

See also: Phase Box

The 4-flap or phase box protects books physically from abrasion and impact and blocks out light. They are virtually always custom made for an individual book. Compared to a clamshell box, it provides nearly the same level of protection from dust and mitigation from sudden temperature and humidity fluctuations.

Materials used include some type of board and possibly an adhesive and closure materials.

4-Flap boxes are ideal for books with a spine width between about 1 cm-3 cm. For books with narrower spines it may be difficult to make folds in the board and /or to accommodate a closure. Larger books may be too heavy for this box style, particularly if the 4-flap is made with lighter weight board. 4-Flap boxes for very large books can be cumbersome, since the unfolded box is five times the size of the book.

Four-flap boxes are typically relatively simple to construct, requiring little specialized equipment and brief training. The risks of introducing an off-gassing adhesive into this enclosure is reduced, since minimal, if any adhesive is required.

• When constructed using 40 pt. or 60 pt. Board, it is often called a phase box and often uses PVAc as the adhesive with a tie or string and washer closure. For these thicker board weights, two pieces of board are adhered together. These can typically be produced in less than an hour.

• When a 4-flap enclosure is constructed of thinner material such as 20 pt. board, it is often called a wrapper or tuxedo box. It may be made of a single sheet of board and avoid the use of adhesives, or may use adhesive to unite 2 pieces of board. A tuxedo box often uses a tab and slot closure. They can typically be produced in about 30 minutes.

• Handmade, cloth covered 4-flaps may be called portfolios. They often are used in combination with another box or have a decorative closure such as bone toggles and loops. They are constructed using a board, cloth, adhesive and paper.

• Commercially produced 4-flaps made of corrugated board may be called portfolios by the manufacturers. They use only corrugated board - no adhesive - and feature a tab and slot closure.

History of the Phase Box

The origin of the term "phase box" is noted by Peter Waters in his 1998 BPG Annual article about the phased conservation concept and program started by the Library of Congress in the 1970s:

"The term phased conservation was first introduced by the Conservation Office of the Library of Congress during the mid-seventies. Throughout this period the word phased was being used throughout the library—to phase in and out, a phased plan for this and that, phased managements strategies, and so forth....

One of the first collections responded to by our phased approach was the European Law collection consisting of thousands of volumes bound mostly in vellum and leather. Most were in such a dilapidated state that every morning one could move along the rows of volumes and sweep up fragments. This was a condition caused by neglect and physical wear-and-tear on the shelves. We eventually boxed this entire collection and made some attempt to estimate and record future treatments. The box design used became known as the phased box. These are not really boxes but wrapper cases which were designed to be used on dormant, rare and fragile collections only. Its utilitarian design is based on the traditional Japanese/Chinese wrapper cases where book volumes have Oriental stab-sewn bindings without stiff covers."

Many libraries have adopted the use of phase boxes as a permanent housing solution, particularly for fragile or damaged items that will not be prioritized for conservation treatment because of their expected low use, duplicate status, the presence of a digital surrogate online, or other factors.

Construction of a Standard Phase Box

Because the term ‘phase box’ is used so ubiquitously, a variety of enclosures are included here as standard. These provide roughly the same degree of protection from light and dust, but heavier boards provide more physical protection. Some instructions cut the 4-flap from a single board, which can be faster to construct but may result in more board waste. While there is a great deal of similarity, institutional preferences exist because of historic practices, material economies, skill of work force, and other considerations.

Author/Source	Board Weight	Closure	Other notes
Harry Ransom Center, University of Texas at Austin Four Flap instructions	10 pt.	None	For use inside a box
Harry Ransom Center, University of Texas at Austin Phase Box instructions	40 pt.	String on front board and washer on fore edge
Harry Ransom Center, University of Texas at Austin Tuxedo Box instructions – no PVA	10 pt.	Tab attached to head of box, slot on front
Harry Ransom Center, University of Texas at Austin Tuxedo Box PVA instructions	20 pt.	Tab attached to head of box, slot on front
Culhed, Per. "The Five Minute Phase Box." Published in the Abbey Newsletter, Volume 24, Number 2. 2000.	Corrugated E-flute, 40 pt., 20 pt. or 10 pt.	Tap attached to fore edge of box, slot on front
Indiana University Libraries. "Phase Box." Tutorial from Indiana University Libraries "Repair and Enclosure Treatments Manual".	60 pt.	String attached to front board and washers on fore edge
Indiana University Libraries. "Tuxedo Wrapper."	20 pt.	Tab attached to front flap, slot on front
Syracuse University. "Phase Box." Syracuse University Libraries.	20 pt.	Tap attached to front fore edge, tucks into box
Library of Congress. "Card Box" and "Phase Boxes": chapters from "Boxes for the Protection of Books: Their Design And Construction".	Various weights	Various designs	Other chapters of the 248 page book include instructions on clamshell boxes
Northeast Document Conservation Center. "Card Stock Enclosures for Small Books."	10-20 pt.	Tab attached to front fore edge, slot at fore edge	Head and tail flaps are not full-book sized
Frieder, Richard. "Designing A Book Wrapper." Published in the Abbey Newsletter, Volume 9, Number 3. May 1985	10-20 pt.	Tab attached to front flap, variations with slot on front or at fore edge
Kyle, Hedi. "Preservation Enclosures." Handout from the 2005 Guild of Bookworkers Standards.	20 pt.?	Tab at front fore edge, tucks into box	Self-closing wrapper p. 46 See also clamshell boxes
Video instructions Upsala University. "The 5-minute Phase Box - part II." Uppsala University Library.	Corrugated E-flute	Tab attached at fore edge, slot on front	Written instructions in the Abbey Newsletter.

Phase Box Variations

See also: Phase Box Variations

Andres, Angela M. 2019. "Wrapper With a Clear Spine." Kenneth Spencer Research Library, University of Kansas Libraries.

Instructions for constructing 20 point wrappers where the spine is made of polyester, to facilitate browsing or for bound volumes on display.

Andres, Angela M. 2019. "Variation on a Wrapper With a Clear Spine." Kenneth Spencer Research Library, University of Kansas Libraries.

A variation on the instructions above, developed for vellum-over-boards bindings. This enclosure features an inner flap that closes over the volume from the fore-edge before the rest of the wrapper is closed. This inner flap helps to discourage the tendency of the vellum-covered boards to warp.

Wedge Shaped Book

The shape of this book prevented it from sitting properly on the shelf. The box's fore edge flap prevents the book from slipping while the box is closed and acts as a fill in the box.

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• Images courtesy of Northwestern University

Multi-Part Object

This volume was accompanied by a set of horn books that are housed in a folder built into the bottom of the phase box.

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• Images courtesy of Northwestern University

Drop Spine or Clamshell Style Box

See also: Drop Spine Box

The drop spine or clamshell style of box is a standard in library collections. They are virtually always custom made for an individual book. They protect books physically from abrasion and impact and block out light and dust. They mitigate sudden temperature and humidity fluctuations. While not water or pest proof, they do provide a first line of defense to both. Because of the way it this type of box is constructed, it is ideal for books over about 2 cm spine width – smaller spines may be difficult to make, fold, and keep closed.

Standard Cloth Covered Clamshell Box

Cloth covered drop-spine boxes are often used for high value books and provide an elegant presentation. Spines can be decorated to resemble the curve of book spines with raised bands and gold tooling.

They are constructed using board, cloth, paper and adhesive and present more variables to consider than corrugated clamshells. For example, if constructed using PVAc (polyvinyl acetate) as the adhesive, they may off-gas acetic acid into the closed box, which could negatively impact the book inside.

Cloth covered boxes require more supplies, specialized equipment, training, and time to produce than many other box types. An average sized box takes about 3-6 hours for a skilled person to construct. If PVAc is used as the adhesive, many conservators allow 2 weeks of drying time to allow the majority of the acetic acid in the adhesive to dissipate.

Instructions

Drop Spine Box includes instructions for construction of cloth covered drop spine box with some functional and decorative variations.

Instructions of cloth covered clamshell and other housings - "Preservation Enclosures", by Hedi Kyle. Handout from the 2005 Guild of Bookworkers Standards. Cloth covered clamshell boxes p. 34-45.

Standard Corrugated Clamshell Box

See Also: Corrugated Clamshell Box

Corrugated clamshell boxes can be made by hand or by machine. Machine made boxes may be hand measured or may be measured by machine. These boxes are an economical workhorse that are commonly used in both circulating and special collections.

Most corrugated clamshell boxes have only one material: corrugated board. Corrugated board comes in different thicknesses. Although some hand produced models require adhesive or cloth tape, the quantity of these materials is low, reducing concerns.

Machine made boxes don’t fold up well for narrow spine widths and some manufacturers set a minimum spine dimension around 2 cm – the exact measurement may vary with the type of board used.

Instructions

Instructions corrugated clamshell and other housings - "Preservation Enclosures", by Hedi Kyle. Handout from the 2005 Guild of Bookworkers Standards. Corrugated clamshell p. 51.

Library of Congress- "Boxes for the protection of books: Their design and construction" compiled by Lage Carlson ... [et al.] ; illustrated by Margaret Brown. This 248 page book includes many housings.

Vendors of custom corrugated clamshell boxes

• TALAS talasonline.com
• CMI archivalboxes.com
• HF Group archival-boxes.com
• Gaylord gaylord.com/box-builder
• University Products universityproducts.com/custom-boxes

See also the AIC Wiki page on Conservation Supply Sources.

Drop Spine or Clamshell Box Variations

• Drop Spine Box with Interior Cradle
• Retrofitting a box for use with ill-fitting or irregular book
  • Books with narrow spine – if a book is large in other dimensions but has a spine under 2 cm, a spacer can be used to make the book fit in a box with a 2 cm spine.
  • Wedge shaped book – If a book is significantly wider at the fore edge than the spine, a wedge may be added to the bottom tray. If the book is larger at the spine, it may be easier to add the wedge to the top tray.
  • Spiral binding – Spiral bindings are larger at the binding than the textblock and often have soft covers. Padding may be added to support the textblock.
• Chemical protection – Anti-corrosive cloth lining to deter silver or other corrosion, microchamber board to absorb odors.

Oversize Book Housings

Quilted wrap - Book Cozy

The book cozy was designed and developed in the 1990s by Mary Baughman, book conservator for the Harry Ransom Center, to provide protection for heavy, large bound volumes (like antiphonals) while in storage and transit within the building. While the book cozy does provide padding and protection, it does not provide support for bindings with structural problems. The book cozies have thus far proven to be a very good solution for the materials in the Harry Ransom Center's collection that have been housed in this way. As for all housings, materials used in construction should be tested and shown to be safe for use in housing collection objects.

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  Book cozies on the shelf

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  Book cozy open

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  Book cozy closed

Instructions

Baughman, Mary. 1996. "Book Cozy". The Harry Ransom Center.

Two-part Box with Sliding Tray

A standard two-piece corrugated box was modified to provide easier access to a frequently-used oversized antiphonary. Modifications include exterior handles and a sliding inner tray with handles to facilitate removal of the heavy volume.

Instructions

Andres, Angela M. 2020. "Custom housing for an oversize antiphonary". The University of Kansas Libraries.

Book Sled

The "sled" is an open-topped housing for an oversized book which is stored flat. It is designed to enable the safe transport of oversized books, and does not add substantial weight to an already heavy object. Inspired by the antiphonary housings at the Newberry Library.

Instructions

Lindsey, Ann. 2019. "'Sled' for 52-Pound Antiphonary". University of Chicago Library.

Other Housings

Wrapping as a Housing

Common Uses

• Goal is to keep pieces together and in order or large quantities such as stacks of unbound newspapers
• Low cost is a priority
• Isolate an object quickly – red rot, old mold found on a dry object
• Temporary protection, for example during a move
• Work will be done quickly or by people with minimal training such as during a disaster

Typical materials

• Shrink wrapping with plastic
• Zip closure plastic bags
• Wrapping with tissue or paper

Possible concerns

• Microclimate inside of plastic wrapping
• Poor quality plastic may become sticky or brittle over time

Dust Jackets

Common uses

• Protecting a publisher-issued dust jacket

• Using a protective dust jacket to protect a binding without a publisher-issued dust jacket

Typical materials

• Polyester film
• Polypropylene or polyethylene (such as CoLibri brand products)

Possible concern

• Microclimate inside of plastic

• Problematic in disaster recovery

Instructions

Gise, Chloe. 2020. "Mylar Book Jacket." Harry Ransom Center, The University of Texas at Austin.

Lace boards

Common uses: An interim housing that is appropriate for an incomplete run of serials prior to binding or boxing of the complete set. This configuration can be used to customize other housing options.

Typical materials: Boards are cut about 1 cm larger than the pamphlets and linen tape is laced through slots cut about 5 mm from the edge and tied to secure the set of pamphlets

Possible concerns: Lace boards are not pretty and provide only the barest physical protection for materials. They will hold a group of thin, soft-covered materials in order, vertically on the shelf. They are usually not considered a permanent housing.

References

Canadian Conservation Institute. Storing Works of Art on Paper. 1995. Government of Canada. Accessed June 9, 2021.

Carlson, Lage. et al. (comp). 1994. Boxes for the Protection of Books : Their Design and Construction. Washington: Preservation Directorate, Collections Services, Library of Congress. Accessed June 9, 2021.

This 248 page book includes many housings for books.

Facini, Michelle. 2005. “Storage solutions for large format works on paper.” In Art on paper : Mounting and housing., edited by Judith Rayner, Joanna M. Kosek and Birthe Christensen. London: Archetype Publications in association with the British Museum. 97-103.

Growler, Stephanie, and S. Russick. Northwestern University Library Boxing Protocol. 2016. STASHc (Storage Techniques for Art, Science and History). Foundation of the American Institute for Conservation. Accessed May 5, 2021.

Kyle, Hedi. Conservation in the Book Arts: Creative and Innovative Solutions. 2005. Brodsky Series Lecture. Syracuse University. Accessed June 9, 2021.

In this 2005 lecture in the Brodsky Series, Hedi Kyle spoke about the development of preservation enclosures and innovative solutions for protecting the myriad of artifacts found in our memory institutions. Many of these enclosures were developed by Kyle herself and combine the stringent needs for safe "preservation environments" with playful origamic structures, something which has also made them very popular with book artists throughout the world.

Indiana University Libraries Book Repair Manual

Kyle, Hedi. Library Materials Preservation Manual. Bronxville, New York: Nicholas T. Smith, 1983.

Melissa. “Poison Book Project”. Winterthur. 2020.

NEDCC Preservation Leaflets. Accessed June 9, 2021.

STASHc (Storage Techniques for Art, Science and History).

This site has information and instructions on housing many types of materials, including books and papers, but focused more on objects found in natural history and history museum collections.

Tasch, Barbara. Marie Curie’s Belongings Will Be Radioactive For Another 1,500 Years. Business Insider, 31 Aug 2015, Accessed June 9, 2021.

Discusses Curie’s notebooks being radioactive and stored in lead-lined boxes.

Tedone, Melissa. Poison Book Project. 2021. Winterthur. Accessed June 9, 2021. \

Discusses toxic emerald green pigment used for book cloth.