TomD
Rust has been a big problem in my shop which is ground level and dry. Humid air, only a day or two a year can cause widespread condensation on surfaces in the shop, and those that are prone to rust, mainly cast iron and some tubing stock can really get wrecked.

Just this spring, I set up a window fan to pull air into the main shop from where it gets hot in the attic area, and this has proved really effective getting the temperature above the dew point at low cost.