I am blessed in that my workshop is an old (150-200 year) cow shed half brick and then ship lapboarding with a high roof and tiled in big old clay tiles its never been air tight ( the windows are boarded) and what ever fast changes of weather and temperature I have never known any condensation, The lathe bed is a place I always check and it never is damp.
I only switch on a gas blow heater when I am in there otherwise jack frost rules in the winter and in the summer its never too hot.
Those old farm builders knew their stuff