How does roof area fit in w. net and gross sq ft?… it can be a different number, esp. if one has large overhangs, covered porches, etc . That’s a different data point to be calculated?
When I look at rough cost estimating on a cost per square foot budget that includes the roof (and everything associated with the project) If there are special considerations, like a large or complicated roof, or porches, or extensive sitework I would either bump up the square foot number or list separately. Generally though, when looking at a cost per square foot estimate it is early on in the project and the goal is not to get the exact construction budget, but instead to get that approximate value so the design does not exceed the area that the client could generally afford. As the design gets more detailed and refined the estimate also gets more refined and I like having a GC be hired for preconstruction services so that they are part of the team while the design and the major decisions are still flexible. Hope this helps.