Want to know everything about framing pastels? Frametek has the definitive article, which you can download below. Frametek makes Econospace, the plastic spacers that adhere to glass and separate glass from painting. Their website is full of good advice dealing with framing.
The company has published an excellent guideline on using their spacers, framing with and without mats, and all about glass, from regular glass to non-glare to UV. Well worth the read.
PSST Blog Author