Our single level house was built in 1930s. Since then at least 2 sections have been added making the house roughly square. We are considering doing an addition and are thinking of going up. The problem is the ceiling heights are not the same. Some are sloped with the roof slope. I do not want to see us lose that feature, but I also want the second floor to be all the same height. So,my thinking is they pull the roof off, build a small wall to the height needed to have a flat and level second floor and then do the second floor, and have the roof allpoint the same ways. Our roof has a lot of annoying valleys. So, can it be done?