Why NOT to use Glass Sandwich Floats in framing

It seems to be all the rage to sandwich art or documents between two pieces of glass, with no matting, creating a see-through area between the frame and the art, showing the wall behind the frame.  Why?

Just so you know,  this is a framers nightmare and a big faux pas for your art!

So when you ask your framer to do this, if they are worth their salt, they should at least try to talk you out of it, and give an explanation as to why this is not a good idea!!

Has your framer ever told you that you should always use mats, or some type of spacing element to get the glass off of your art, photo, document, etc?  What happens to art when framed without the necessary spacing and two pieces of glass?

First off, your framer has no way of properly mounting the document to the glass, so he will either just lay it in and hope that it won't move (it will eventually slip), or put a two sided tape or glue along the top of the back side of the document.  This still does not guarantee it won't move, and definitely ruins the value of your art.  Not to mention the difficulty of taking it out, if and when you want to reframe it because you no longer like this look.

With temperature changes in your home or office, such as your art hanging in sunlight on the wall, summer to winter, air conditioning, the use of humidifiers, and heat temperatures fluctuating while using a furnace,  the environment in your home is continually changing.  Although making us comfortable, this makes our art contract and move and the glass sweat.  This is generally not enough to see the condensation, but is enough to get moisture into your art.  This moisture has no breathing room therefore creates a perfect environment for mold and mildew.

The darker spots on the left of this photo and
on the left of the paper tear
are mold spots. 

The funny thing (or not so funny thing) about mold is that it is alive.  A living, growing organism.
And once it permeates the paper, it is impossible to slow down without treatment.  Even then, you may never get it's growth in the paper completely stopped.

Have you ever bought a photo frame, slipped in a photo, set it on the shelf for a couple years,  and then decided to retrieve the photo to make copies and find it stuck to the glass and ruined?  Although it has been sitting on a perfectly dry shelf, with no water or moisture anywhere near it, somehow it got wet.  This is the condensation from room temperature changes.

This old museum lithograph, of the famous "Les Demoiselles d'Avignon" oil painting created in 1907 by the Spanish artist Pablo Picasso, was placed between two pieces of glass years ago.  The art had slipped from its original position, and needed to be repositioned.  However, the method of the previous framing proved to be detrimental to the work of art, causing condensation to form along the bottom side of the print.  This caused discoloration, mold, and the art to get stuck to the glass.  It actually was a good thing the framer did not tape or glue it to the back also--if this piece had been stuck on both sides (front and back) it would have been next to impossible to retrieve it successfully.

I offered to take this piece to a conservationist to see what they could do with it,  before attempting to remove it from the glass.  But after examining it with my client, she decided to let me remove it, and we decided to just cover any damage with a mat.  Having liked the piece, she still wanted to hang it in her house.  Although I did a fairly decent job (with the help of an employee holding the glass off while I released it) of removing the art without completely destroying the piece, you can see there was significant paper loss (above photo).

After giving this old guy a mold treatment, flattening it with humidity,  framing and covering the damage with matting, it now looks like this.  It is ready to hang and be enjoyed in my client's home, but what value it had has been diminished.