Museum Quality Conservation Mounting
When considering a mounting choice for your artwork, it is essential to understand the options, techniques, and materials involved and how they will affect the art and its value over time.
The ‘mount’ is made up of several distinct elements, including the window mount (or mat), the undermount (or back mount), and the hinge (or binge). To provide the correct support and protection from environmental exposures, the window mount and back mount must be between 1 and 2 millimeters (4ply) thick at minimum. The hinge should typically be along the top edge to allow the paper to hang and breathe naturally and should use a conservation quality white paper tape or linen tape. Never use commercial tapes (masking tape, Scotch tape, etc.) or pressure sensitive tape.
The Mount Board
Choosing the correct type of mount and backing board is essential when you are dealing with any work of art that you wish to last for decades or that holds any value, either inherent or sentimental. The mount (and mat or window mount) are the elements of the framing design that are directly in contact with your artwork over the life of the piece, so never, ever skimp on the quality of the mounting for your artwork.
There are three primary grades or levels of mount board to consider:
Museum Grade – The highest quality material available, it is designed for permanent framing of valuable original artwork with an eye to long-term conservation.
- Cotton Rag Board – A sold core 100% cotton fiber board is the highest quality mount material available. Unlike wood pulp papers, cotton rag mat does not require acids to break down the fibers for use, so they are conservation quality and will not harm or burn the artwork they are in contact with. While not required to be buffered, some cotton rag board does use alkali buffering* that can prolong the life and stability of the board and add extra protect for certain types of art.
Conservation Grade – An intermediate level of materials designed for framing works of art, prints and photographs that may have a lesser value and are not intended for long term conservation.
- Conservation Board – This type of mounting and matting board is made from wood pulp papers that have been chemically treated to reduce the acidity levels and then treated with a layer of alkali buffering* between the artwork and the paper. This is an intermediate quality material not intended for very valuable art.
Standard Grade – These mount materials should never be used for any work of art which is expected to last or that has any value. The materials in this grade of mount will damage any art it is in contact with over time.
- Standard Mount Board – This grade of material encompasses a wide range of possible materials and boards that are not acid-free and not of conservation quality that will damage your artwork over time. Un-treated wood pulp papers, cardboard, commercial papers, and other materials of this level should never, ever be used in the framing of fine art. Damage and loss of value will result.
* A Note on the Mounting Photographs – Some types of photographs may be negatively impacted by the alkali buffering used in certain mounting materials. A true, un-buffered 100% cotton rag board is highly recommended for any and all photography to be safe.
The Hinges
- It is important when hinging fine artwork not to restrict the ability of the paper to breathe. All papers, to some degree expand and contract with changes in humidity and temperature. Mounting artwork in a manner that restricts this movement can result in damage to the paper. The art should be hinged along the top and allowed to hang naturally.
- Any tapes and adhesives used to hinge or mount fine art should be free of materials and chemicals that will stain or damage the paper, and be fully removable at a later date. Commercial tapes and pressure sensitive tapes (masking tape, Scotch tapes) that are not designed for museum quality conservation will leave sticky residue, staining, and be difficult to remove without severe damage to the paper. Use only conservation grade tapes and adhesives.
- Water-soluble conservation gummed white paper mounting tape is acceptable but pressure sensitive archival conservation tapes are not recommended for use directly on the picture.
Talk to an art and design expert at any of our nine southern California custom-framing stores for more information on conserving and protecting your fine art.