I have found that I am not going to be able to build a 2 car garage sized workshop building at my new location as I had intended, because a town water line runs right across the area and I can't put in a foundation or cover it. What I will have room for is a 14 or 16 foot wide building, and I am thinking of making it 28 or 32 feet long. Something like those portable garages on skids that companies and Amish people sell, but without the big door. My question is how the base or foundation is built. My impression from some reading is that pressure treated skids are used, running lengthwise, and then 2x6 treated joists on 12" centers are run across them, (treated?) plywood is used for the floor and from there it's an ordinary stud frame. What I don't know is how they go about joining lengths of wood to make the skids, and how many skids and of what size are needed for a given size of building. I prefer to overbuild rather than underbuild, usually. I can imagine using 4x4s with 2x4s on top to join them together, but that seems like it would be weak, or using 2x6 or 2x8 standing on edge in 3 or 4 layers and staggering the joints, but again I don't know if that would be enough. I'll be very grateful for any insight into how this is normally done.