Oil Painting Under Glass


I have just purchased a large oil painting from
1890 which I believe to be valued at approximately 8000.00.  I am entirely
inexperienced in art work, and my question is this—-The painting is
matted and framed under glass.  Am I correct in believing that the more
appropriate way to display and preserve the painting is exposed to the air, and
not under glass?  What would you advise?

Thank you for any help you can give.

Normally oil paintings are varnished and framed without glass, but not because it is a better way to preserve them.  It is not unusual to see very valuable or sensitive paintings framed behind glass (the Mona Lisa is a famous example of this).  The varnish serves as a protective layer so the painting can be cleaned without damage, but it only protects the surface of the painting.

If it is framed behind glass this may indicate that it would not be safe to expose it to air.  Perhaps the painting is done on an unstable surface like paper or cotton that would deteriorate much faster if exposed.  It may also be that the painting cannot be cleaned as it is too sensitive to solvents, or glass was simply chosen instead of varnish as a protection.

In any case, any painting will last longer under glass, it just may not display as well.

Hi David

Is it a bad thing to frame oils behind glass; I have heard
that it will make the painting “sweat” and it is not a good idea
for investment art.  Is this true?

Regards  Sandy

It is not really a bad thing, just unnecessary for most varnished oil paintings. I have never heard of an oil painting ‘sweating’ though it might do something similar if it wasn’t completely dry before being put under glass.

Hope that helps.  David


Posted in: Oils