The following information is from a post by Laura Shelley, on the Wet Canvas forum. I’ve modified this a bit to fit my own style of work, but it’s a handy reference to use if you decide to go with a professional framer to get your painting ready to hang. If you’re planning to frame it yourself, here’s a great how-to from Sheila Evans (whose art is absolutely wonderful, worth the visit in any case).
Care of Your Pastel Painting
by Laura Shelley, Wet Canvas forum
Your new pastel is a hand-painted work of fine art. I use the best archival materials for its creation. If properly taken care of, your painting will last for many lifetimes. Pastel is one of the most permanent art mediums in existence. Many pastels painted over 200 years ago are still as bright and fresh as the day they were created.
The artist’s pigments in my pastels are the same as those used in fine oil paints. The only difference is that with pastel the pigments are not mixed with a liquid binder which may degrade over time. The pure, bright hues will not change or yellow.
Your pastel painting may shed a few particles of pigment when new. This is normal and will not damage the image. The surface will become more solid with time and shedding will stop. Please do not attempt to rub or brush away fallen particles, as you may mar the surface of your pastel. Lightly shake them off and store your unframed pastel flat until you take it to your framer.
Framing: You will receive your pastel in a custom-made protective foam core sandwich. This is fine for short-term storage, but to protect and preserve your painting while it is on display, you should have it professionally framed behind glass. Please choose your framer carefully. Discount framers may charge less, but they often save money and cut corners by using non-archival, non-acid-free framing materials. These materials may harm your pastel. It’s worth choosing the best quality framing materials so that you can enjoy your pastel for many years to come.
What to tell your framer
You want acid-free, archival framing materials. The backing board and mats, if any, should be museum quality. 100% rag board and acid-free foamcore is best. Cheap mat board or brown cardboard backings will stain and yellow your painting within a few years.
Do not spray any sort of fixative or coating on your pastel in the framing process or allow your framer to do so. Fixing may change the colors in your pastel, damage the paper or dislodge the pastel particles from the surface. Careful handling is a must.
Do not touch the painted surface. Putting fingers or other items on top of the painting or allowing it to be rubbed or flexed will damage the surface. Keep it flat, supported from underneath and facing upwards to protect the pastel surface.
Choose a framer who is experienced in working with fine art pastels. A framer who works mostly with posters and printed reproductions or oil paintings may not realize that pastels take special handling. Do not risk the welfare of your pastel in the hands of an inexperienced framer.
Do not use Plexiglas™ or non-glare glass to frame your pastel. Plexiglas™ holds a static charge that may pull pastel particles from the paper and in time create a “ghost” image on the underside of the glass. This will probably not seriously harm your painting, but it will obscure your view of it! Non-glare glass makes your painting appear blurry and dull in color, and it is best avoided.
One good approach for framing your pastel is to use a reversed double mat, with the larger window underneath. This creates a gap behind the mat where any fallen particles will be invisible. Another is to use a spacer strip between the glass and the painting so that no mat is necessary.
Hanging your pastel
Choose a dry place indoors out of direct sunlight. Sunlight, even filtered through a window, is the enemy of all fine artwork. It degrades paper and canvas and may fade pigments. Dampness may damage paper and even allow mold to grow on paintings. Outside walls, basement walls and stone or concrete walls may transmit dampness, so avoid hanging art on them. An interior wall without nearby windows is ideal. Bedrooms, sitting rooms and hallways are often the best places for fine artworks. Bathrooms and kitchens may have very damp air, so please avoid hanging your fine artworks near showers, tubs and stoves.