I live in Western Oregon, and in my location we get over 50" of rain a year. Just 10 miles away as the crow flies a radar station on the top of a 3,000 foot mountain recieved 16 FEET of rain in one year, and a logging company town about 15 miles away averaged 12 feet of rain per year over 50 years!
We have a lot of moisture here, and I have found that a well-weatherstripped, unheated shop with a concrete floor will result in rust if bare steel is not coated with paint, wax, or a preservative coating of oil/grease/cosmoline/engineered "coating". The greatest effect is when we have freezing temperatures for several days that cold-soaks the metal, followed by a warm front off the Pacific Ocean that warms things up to 40- or even 60-degrees with a very high humidity. Everything "sweats" by condensing beads of moisture from the damp air.
The solution for this is keeping interior temperatures at least 40-degrees, and 45 is better. Not much advantage in keeping it more than 50-degrees inside.
In places of high humidity combined with higher temperatures, this does not apply. However, it you live where there are "sweating" cycles, it offers a way to counter them.
! 
