Yes, most barns here are built of timber, and then treated with linseed oil or other things to make them a bit more weather resistant. I've seen a few stone barns, but they're more rare in this part of the world. I'm not an expert on barn foundations, but I think some are built on poured concrete slabs, for stability. Not sure about some of the older ones, though, but it's a great question! Thanks for stopping by! 😊