John, most of the older mobiles were constructed using 2x2 lumber for the walls. And 10' wides haven't been made for a long time so I'd think yours are probably 2x2s. Not a good idea to add weight to it by putting a heavy roof on top of the old one. However, I have set 4x4 post on the outside of the mobile walls and built a free standing roof over the mobile. No added weight on the mobile. I have also seen a metal roof kit that fits over the old roof. I just wish I could remember where I saw it! I'm sure it was in a mobile home supply book but I don't know where it was from. Sorry. Hope the little information that I did have helped.