it's a prefabbed building then assembled on site, at least the walls, the roof trusses where put up one by one then the roof sheathed. took them about 2 days to put it up. It's on a Slab and a course of 8" block around the base.. pretty solid unit. didn't cost me 1/2 as much as the one Joey was looking at at Home Depot. Gotta love small towns and desperate contractors looking for work.