Subscribe or Renew Membership Subscribe Renew
douglasso's picture

  I am turning a former garage into an addition to the master bedroom. The garage floor is 12'x12' and slopes from 3" to 5" lower than the slab in the bedroom. I dug out the corner of the house and the thickness of the perimeter of the slab is 16". In the inside there is a level chain wall around the area that the framing sits on. I was going to level the concrete over from that to the existing slab. I live in Louisiana in a house built in the 70s and I am almost certain that there are no piles under the slab. I was looking to add styrofoam strips to the slab (anchored of course) before concrete; to keep the weight down. I was wondering what the slab thickness should be on top of the styrofoam; for foot traffic only and should mesh rebar be used? If there is anything else that you think I should do... I'm all ears. Thanks a lot

Well, your idea of turning a (post #211083, reply #1 of 3)

Well, your idea of turning a garage is very nice. But I think the thickness and perimeter are very low. You  need not to dig out the corners, yet you can include it inside the wall.  The plan you have made seems to be little complicated and it will create a little mess. And you need a cleaning service professionals like 


this company from Long Island I attempted to insert a spam link.

I would just put tapered (post #211083, reply #2 of 3)

I would just put a vapor barrier dow, put  tapered sleepers down, insulate with foam board, and put subfloor on top.

Don't pay attention to the cleaning spammer, although he is better than most with his english.

You're going to have to live (post #211083, reply #3 of 3)

You're going to have to live with wahtever you do for a long time so nows the time to do it right. I don't like slab on slab for a bunch of reasons nor do I,like sleepers and plywood over sloping slabs since the lower end at ground level can flood. Taking out the existing slab is not a big deal and will aloow you to insulate, run electric, pour footers or pretty much anything else you will ever want or need. Do it right once and you'll never have to think about it again.

Florida Licensed Building Contractor, 50 years experience in commercial remodeling, new homes, home remodeling and repairs and all types building maintenance.