Don Phillipson wrote:
....

Humidity is an important factor. Dry N.American air has
caused cracks in a lot of European furniture (usually in large
thin, flat panels.)
....

Well, sorta', but...

Generally, where the problem arises is in taking a piece and introducing
it into a heated, tightly sealed house w/o additional moisture
compensation. In winter in forced air heating, inside RH can drop to
the single digits pretty easily.

In an unheated space, there's not the heating of cold air causing such
drastic drops in RH and so moisture will stay more nearly in
equilibrium. As another noted, it's perhaps more likely to be a
condensation or similar problem if it's too high.

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