In a childhood i spent some time on an old German farm with a main house and a barn. I crawled and climbed everywhere in the both buildings. Both buildings are of the same high quality of build - brick and stone walls, pitched red ceramic slate roofs, large wooden beams - that is tested by and evolved over long time. The only noticeable difference between those 2 buildings was that the barn had less windows, and the first meter of its wall height was made out of the larger stones fit tightly to each other whereis main house wall were fully brick and such stones were making only the foundation - thus the barn walls were about 2 times thicker at that lower height part. I didn't see any metal in the construction - in the attic the wooden beams were dovetailed in the joins and the joins were pierced by large thick "nails" made of hardwood. Smaller members were tightly dovetailed to or sat in the grooves of the larger members - all the way down to the planks which formed the sides and the floor of the attics (and the second layer of planks about 4 inch below the attic floor planks was the ceiling of the first floor - again sat tightly into the grooves of the large beams).