I built a 30'x40' storage barn about 10 years ago, long before I even thought about owning metalworking machinery. The barn is mostly used for lumber storage for my cabinet shop, and for toy storage (camper and sailboat). I've sold the sailboat a few years ago, with no intentions of getting another. In the last few years, metalworking tools have been finding their way into the barn. Now that I've seen how quickly humidity and temperature changes can make rust blossom on equipment, I decided it was time to keep them in a more climate controlled room. I can't afford to heat the whole barn, so I'm going to build a 12' x 24' x 8'6" high shop inside the barn. This will leave room for my camper, my lumber and a utility trailer in the unheated part of the barn. Here is a "before" photo of most of the barn. The camper is buried for the Winter, but will only be blocked by a utility trailer in the Summer months.
I have all the studs pre-cut to size, so I just have to cut some boards to match the floor contours for under the walls and then I'll be throwing up some wood. I'll post some photos along the way.