Framing Talk

Anyone who has renovated an old house or been saddled with a leaky condo knows all too well that dreadful things can hide behind the smooth-faced surfaces of plaster and drywall. The same is true of framed art – who knows what evil lurks behind that plain brown dustcover?
If your art was framed before 1980, you can be pretty darn sure there are some conservation no-no’s like acidic matboard, cardboard, and horrible paper staining tapes in there. Even with more recent framing jobs, it’s quite possible that cost-consciousness and/or ignorance have put your art in a less than optimal environment.

To complicate matters, there are different standards of quality that even the best framer may work to. The perceived value of the art, cost conscious clients and the framer’s bottom line can all affect the job you will get. There is no one correct way to frame art on paper, and your best chance for getting  a job that will protect your art is to become familiar with the basics of framing materials and methods.

Overview of Framing Components:

Glazing Glass

  • Regular Glass: filters some UV light*, has a green tinge
  • Specialty Glass: offers increased visual and protective options such as lamination, greater UV filtering*, optical clarity, anti-reflective coatings or anti-reflective etched surfaces

Advantages of Glass:

  • Vapor Barrier
  • Relatively affordable depending on type chosen

Disadvantages of Glass:

  • Heavy
  • Fragile – should not be used for large pieces unless laminated

Acrylic Sheeting

Regular: filters some UV light*
Specialty Acrylic: offers options such as increased UV filtering* (which gives a yellow tinge), anti-reflective etched or coated surfaces, anti-static coatings, anti-scratch coatings

Advantages of Acrylic:

  • Relatively light weight
  • Shatter resistant
  • Available in different thicknesses

Disadvantages of Acrylic:

  • Easily Scratched
  • Static Charge can build up easily
  • Bows

*N.B. UV Filtering will not prevent damage by visible light, which can be considerable


The matting (and frame) should be larger than the artwork to allow room for the art’s expansion during times of elevated humidity.  If there is no expansion room,  art can become irreversibly rippled. The amount of expansion room given will vary according to circumstances.   If it is not possible to provide this room for expansion (e.g. original frame) framing should be sealed (see Sealed Framing below).

Window Mat

The function of the window mat is to keep the artwork from touching the glazing.  This is especially important when glass is used, because glass’s high temperature conductivity can allow moisture condensation (encouraging stains and mold growth) at points of contact.  Acrylic glazing has lower temperature conductivity so does not cause condensation, but static can pull loosely adhered pigment particles (e.g. pastel) from art.  Both acrylic and glass can be hazed by oxidizing oil based printing inks and other uncured media so keeping distance between glazing and art is desirable.


  • Rag or Alpha Cellulose only
  • Non-bleeding dyes only
  • Choose Bainbridge “Artcare” when framing acidic or unstable artworks.  Artcare contains “Microchamber” zeolites that absorb and sequester volatile acids, peroxides etc. that the art may emit.
  • Choose 8-ply matboards for 3-D pieces (e.g. pieces with paint impasto, paper distortions, collage elements); additional 4 or 8 ply boards can be added for extra height

Foamboard underlays to increase space between art and glazing are not recommended for valuable or important items due to foamboard’s potential  for outgassing.

In some cases a window mat is undesirable or impractical.  In these cases spacers should be used to keep the glazing raised from the artwork.

Back Mat

The function of the back mat is to support the artwork.  The larger and heavier the art, the sturdier the back mat needs to be.

  • Use rag or alpha matboards with same qualities as those used for window mats.
  • Choose 8-ply for larger pieces that need support.

Substituting foamboard, even acid –free foamboard,  for a back matboard is not recommended because it can warp and may outgass damaging chemicals.

Securing  Artwork in Matting

Non Adhesive Methods

  •  Sinkmount with overmatting.  Artwork sits in a well in the backboard (cut like a windowmat).  The well  is cut large enough to allow for paper expansion.  The art is held in place by the window mat which overlaps the edges of the art.
  • Edge strips.  Polyester film (Mylar) or paper strips attached to backboard overlap the edges of the art, holding it in place.  Extra security is given by the window mat which also overlaps the edges of the artwork (and generally covers the edge strips).
  • Photo corners.  Polyester film or paper corners attached to backboard hold art in place.  Used with window mat that generally covers the photo corners.  Photo corners may not provide enough support for large and/or very light weight papers.
  • Encapsulation  between sheets of polyester film  (Film sheets joined with double sided tape or by welding).  A polyester film overlay can also be used to hold art to backmat using double sided tape.

Adhesive Methods

  • Japanese paper and wheat starch paste hinges.  Many possible hinge type and placement variations. Wheat starch paste is well known for its good aging properties.  The artwork’s paper support  can however be altered or damaged if the moisture content of the paste is too high. The framer should have some experience using wheat starch paste.
  • Commercial pressure sensitive tapes are often used but not recommended because their aging properties are unknown and their chemical compositions are proprietary and can be changed without notice.  Filmoplast P90 has, to date, shown reasonably good aging properties.
  • Commercial moisture activated linen and paper tapes are generally too strong, can discolor or stain paper, and can be difficult/impossible to remove.  Paper can be altered or damaged if too much moisture is used during application.

Adhesive Method for Float Mounting – Pass-Through hinges

Used when it is desirable to show edges of artwork.

  • Japanese paper and wheat starch hinges are applied to reverse of the art (leaving small gaps between the edges of the art and hinges so that the hinges are hidden.)  Free ends of hinges are threaded through razor cuts in the backboard and pasted to the reverse of the backboard.

Sealed Framing

Useful for water sensitive items (e.g.items that cannot be repaired should they be water damaged such as screenprints, water sensitive dyes, some pastels). Also useful to protect artworks from uncontrolled environments (e.g. locations with high or rapidly fluctuating Relative Humidity).

  • Framing package (glass, matted art) is conditioned to RH 40 – 50 % and lain face up on a sheet of Marvelseal 360 (flexible aluminum/polyethylene laminate) polyethylene side up . Edges of Marvelseal are wrapped to front of glass and secured with electrical grade hot glue or 3M# 979 ATG tape.  Corners are pleated and heat sealed in place; dabs of hot glue can assist in sealing corners.

Back board

Placed behind back mat to add rigidity and provide a barrier to the outside environment.

  • Foamboard
  • Advantage:  Light weight, reasonably chemically stable.
    Disadvantage:   Warps.

  • Coroplast
  • Advantage:  Light weight, chemically stable, water resistant.

  • Corrugated Clear Acrylic Sheet
  • Advantage:  Light weight, chemically stable, allows gallery labels on reverse of original backboards to be seen.

    Frame Closure

  • Staples, brads, or points secure framing package/ backboard to interior sides of frame.
  • Edges should be sealed with barrier tape (e.g.Lineco Aluminum Frame Sealing Tape) to keep dust, insects and air pollution from entering frame. Barrier tape also gives some protection from water damage.
  • If there is space, a wooden strainer  screwed into the sides of the frame can be  used instead of staples or points.  (Barrier tape should still be used).  This gives more even pressure and a tighter fit to the backing board and framing package.    A Coroplast backing board with strainer gives much greater protection against water damage than conventional foamboard/staple/paper dustcover frame closures.


    Often used to seal and “finish” the back of framing package.  May be paper or the more protective Tyvek.  A dustcover is unnecessary if the back of the frame is tightly sealed (e.g. aluminum frame sealing tape)  but is a traditional method of finishing a framing job

    Hanging Mechanism

    Often plastic coated wire and D rings screwed to the reverse of the frame. Self leveling brackets such as “Wall Buddies” are also available.  Hanging mechanisms are rated for their weight bearing capacity and should matched to the weight of the finished framing package.

    Thanks to all of my framing friends who have introduced me to, and instructed me in,  the mysteries of the frame! 

    Rebecca Pavitt
    November 19, 2013