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Works on Paper

There are six elements that comprise an archival picture frame. You may want to use all or only some of the elements. You may purchase all or any one of the elements from the supply sources listed on this site. 
The six elements that form the frame package are:

1. Frame

This is the wood or metal moulding that surrounds the art package. This is the most important element, and the only one always present. An oil painting on canvas, for instance, will probably have only a frame. A photograph, on the other hand, will usually use several of the elements- frame, glazing, mat, and backing.

Choose a profile (shape) that you find pleasing, and has enough rabbet or channel space to contain all the elements you plan on using. If for instance you are using:
Acrylic glazing (1/8th inch thick) and
4 ply window mat (1/16th inch), and
Foam core backing (3/16th inch)
You’ll need at least 3/8th inches of rabbet space:
(1/8th + 1/16th + 3/16th = 3/8th inch).

Frames are ordered in inches and fractions. The size of frame you order depends on your art package. Are you framing a canvas and nothing else? You will measure the canvas from top to bottom and side to side. Are you framing a photo in a window mat? Measure or calculate the mat dimensions from top to bottom and side-to-side. The frame will be chopped to fit those dimensions- the rabbet or channel space will measure slightly larger than your art package.

2. Glazing

This is the glass or acrylic (such as Plexiglas) that protects the art. How to choose between the two?

Glass is cheaper and more scratch resistant.

Acrylic is lighter and more break resistant.

Westfall Framing only sells acrylic, but if you prefer, glass is easy to acquire locally. “Single Strength” is usually sufficient. When you order glass, specify that you need the size cut “exact”.

Westfall Framing sells two kinds of Acrylic:

– Regular is considered standard and is suitable in most instances.

– Ultraviolet Filtering is suitable when framing extremely valuable pieces, or when exposure to direct sunlight is possible.

Generally speaking, everything needs glazing except paintings on canvas.
Order your glazing at the same dimensions as your frame.

3. Glazing Spacer
Sometimes you want to “float” your art, or mount to a backing and forgo a window mat. This is common for watercolors. Or perhaps you have a lot of surface detail, such as a collage, or a mixed media piece with spoons and monopoly game pieces glued on. You need glazing space, or separation between the glazing and art. Westfall Framing offers a glazing spacer specially designed for the Museum Hardwood Frames, available in matching wood types. We also offer two profiles of metal frames with built in glazing spacer.

The Museum Hardwood Frame glazing spacer (HW16) is tacked into the frame after the glazing and before the art and backing. It MUST BE ORDERED WITH A MUSEUM HARDWOOD FRAME, and is ordered at the same size. 

The metal frames with glazing spacer (N44 & N55) have a separate channel that holds the glazing, and is assembled just like the regular metal frames, with the glazing inserted in one channel and the art and backing in the other. There is no additional ordering information.

4. Backing Mat
This is simply an additional piece of mat board to which the art is fixed, usually two ply. It is common to mount the art directly to the backing board, but you should keep in mind that whatever your artwork is mounted to essentially becomes part of the artwork. If your backing board is damaged, for instance, you’ll probably want to detach the artwork and re-mount it. This can be difficult, particularly if you have spray- or dry vacuum-mounted. The backing mat is especially wise if your art will be travelling- frequently handled art isfrequently damaged art.

The highest level of archival conservation does call for a backing mat- but Westfall Framing does not recommend a backing mat for every application. Considering the work’s value, the expected life span of the piece, the potential for frequent handling, and even whether it may be reframed can help you decide on the backing mat.

5. Window Mat
A mat board with a hole cut out, through which the art is visible. Commonly used with photographs and prints. The standard mat thickness for a window mat is 4 ply, or about 1/16th inch, although 8 ply is sometimes used for very large pieces. Double matting is also common; this is usually two 4 ply mats with the top mat window cut at least 1/4 inch larger on all sides.

There are 3 sets of dimensions that apply to a window mat:

  1. THE OUTSIDE DIMENSIONS, which will correspond with the size of your frame, glazing and backing. 
  2. THE WINDOW DIMENSIONS, which is the size of the hole. This is determined by the size of your artwork. The window can crop the piece or extend beyond the image area, but it always extends at least a 1/4 inches into the paper. You do not want the edge of the paper to be seen when using a window mat.
  3. THE BORDERS, which are the most subjective. A rule of thumb says borders should be at least 2 inches. Another rule of thumb says that you cannot have too much of a border. Side borders should always the same size. It is common to “weight” the bottom border, or make it larger than the top. This is because of an optical illusion that causes a bottom border the same size as the top border to appear smaller. This phenomenon is more distinct as pieces grow larger, and it is also more common to pictures oriented vertically. It is not, however, incorrect or problematic to simply center the image. Also, borders do not necessarily need to be consistent. A picture will look fine with borders that are, for instance, 3 1/2 inches top, 3 3/4 inches bottom, and 3 inches sides.

You can figure your borders two ways, but either way, you need to know the window size to start.

The first method starts with the frame size, for instance a 24” X 20”:
Standard Frame Size Formula
Frame Size
÷ 2
Height 24"
Width 20"
10" ÷ 2
9" ÷ 2
5" Top, 5" Bottom
4.5" Side, 4.5" Side
Height 24"
Width 20"
11" ÷ 2
11" ÷ 2
5.5" Top, 5.5" Bottom
5.5" Side, 5.5" Side
Height 24"
Width 20"
10.5" ÷ 2
11.5" ÷ 2
5.25" Top, 5.25" Bottom
5.75" Side, 5.75" Side

The second method starts with the borders you want:
Custom Frame Size Calculation Forumla
Window Dimensions
Border Dimensions
Frame Size
Height 15"
Width 12"
3" Top + 4" Bottom
3" Side + 3" Side
22" Height
18" Width
Height 20"
Width 16"
5" Top + 5" Bottom
5" Side + 5" Side
30" Height
26" Width

A series of different size pieces displayed together look best with a standard frame size and variable borders. Start with an optimal frame size and the dimensions of your windows, then calculate the borders with the “Standard Frame Size Formula” above. For a weighted bottom, subtract a little from the top and add it to the bottom.

A stand-alone or uniquely sized piece may benefit from a custom size frame. To determine that size start with the dimensions of the window, then choose your ideal border sizes. Use those dimensions and the “Custom Frame Size Calculation Formula” above to determine the size of your frame.

A GENERAL NOTE ON ALL MAT BOARD. There are many different varieties of mat board, usually made from either wood pulp (paper), or cotton fiber (rag). The important detail is the acid content of the mat, since acid can bleed from the mat and discolor artwork. Westfall Framing handles only 100% cotton rag mat, acid-free, solid core (same material throughout), manufactured to the traditional conservation standards.

6. Backing Board
The last piece in the art package, it should be some type of stiff material to provide support. It is also what protects the back of the framed art package. Materials used for backing board include cardboard, foam board (also called foam or fome core), and gator board, and are available in a variety of thickness, from 1/8th inch up to 1/4 inch.

It is common to mount the artwork directly to the backing board. This is acceptable framing technique in most instances (see BACKING MAT). It is not acceptable to forgo a backing board when a backing mat is used. Framed canvases usually don’t have a backing board since they don’t require support.

Westfall Framing sells 3/16th inch Foam Core, both regular and acid-free. The regular is cheaper, and has a clay coated acid-free backing on both surfaces. The acid-free is just that, but more expensive. When using a backing mat, it is in most instances acceptable to use regular foam core. Artwork can be mounted directly to acid-free foam core with all confidence regarding acidity. Mounting directly to regular foam core? It is frequently done. We have no comment regarding its long-term safety.