Temperatures that damage paintings
by Miles Lewis
(Woodland Hills, CA, USA)
Reader Question: I've found from a few sources that an acrylic painting can develop a weak paint film if applied/allowed to dry in temperatures of 40F - 50F or below. This period is indicated at about 8 days. Is there any structural danger in keeping fully dried acrylics in temperatures between 20F - 50F?
Your sources are correct that it is ideal to allow acrylic paintings to dry in temperatures of 50F (10C) or above for at least 8 days, to ensure that the acrylic paint has dried all the way through. Likewise it is preferable to create the painting at 50F or above, because colder weather may cause microscopic ice crystals to form on the paint which can make the paint unstable.
If acrylic paintings are stored at really low temperatures (40F / 4C or below), the paint film will become brittle, which could result in damage. Some sources say even 50F / 10C is too risky. The ideal temperature for storing paintings is room temperature, between 60F and 80F (16C - 26C). As a side note, it is generally recommended not to store acrylic paints at freezing temperatures either.
Stability in temperature is also important for acrylic paintings, as sudden rises or drops in temperature or humidity can upset the balance of the paint film.
In general, I'd suggest not taking the risk of storing acrylic paintings at temperatures as low as 20F - 50F (-6C - 10C) and instead, store the acrylic paintings at constant room temperature with low humidity.
Hope that helps!