I've also been curious about this as well. It seems a small house will use quite a bit of steel (usually a few tons) depending on the design, number of levels, and the roof type. Its easy to overlook if its just rough guess. One useful item is to have a steel estimating done professionally. You know then exactly how much steel to buy and can usually save on some costs in the process of having to order lesser amounts of steel. Has anyone built a small house recently? What was the, incidence of actual vs estimate steel ordered?