Different types of artwork need to be framed in different ways this is generally because of the materials that have been used to create the masterpiece. Whether it is a drawing that your child made at school, an art class you have been attending or a watercolour you have inherited, you will need to look into the specific ways to frame that particular type of artwork.
For example, if you are framing a piece of art that has been made using charcoal or pastels then they need to be framed behind glass. Your professional framer will tell you that Perspex is not a good idea to use because it can create static energy that will draw any dust from the artwork towards the surface of the Perspex. Having a spacer such as a picture mount or a small strip of wood separating the artwork from the glass is advisable so that any dust particles can fall freely to the bottom of the frame.
When framing most things, you don’t want the artwork to be pressed against the glass. Overtime it can cause problems, especially if you want to change the picture frame and glass. The artwork can stick to the glass if there is any moisture inside the frame and ultimately destroy the piece of art.