We don't do a very good job of recycling and reducing and reusing when it comes to building. At our new house, the workers try to order the right sizes of materials and they try to begin and end things in ways to use the whole product, but materials do need to be cut and trimmed to fit. They keep piles of scraps around to pick from when they need smaller boards instead of cutting off a fresh one. The lumber yard takes back the odd lots of unused stuff and puts it back in inventory. There is a lot of material just used in packing and shipping but it needs to be used to prevent the items from being damaged, which would be even more wasteful. The workers save boxes of soda cans to take home to recycle and they saved out some of the smaller pieces of aluminum trim but an awful lot of wood and cardboard and metals and plastics and other materials end up in the giant dumpster that has been emptied already and nearly refilled. I don't have an answer but I wish we did.