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Floor leveling

I have a room that used to be outside and is now inside (part of a patio that was walled in). It has a severely sloped concrete floor (higher on one side by 2 inches) because it was outside (for drainage). The two methods that I can think of that will work are 1) pressure treated sleepers that taper from 2 inches to nothing or 2) some kind of concrete leveling. The room is approximately 19 feet by 9 feet with the slope along the 9 foot plane. Any suggestions or comments would be appreciated. Thanks.

Re: Floor leveling

Are there moisture issues you are worried about? If not, then the PT sleepers would be a bad idea as PT lumber does a bunch of nasty things as it dries out unless you use KDAT lumber which is pricier.

What type of flooring are you planning for the wear surface?

A mudded floor that large isn't a DIY project unless you have 3 or 4 large, able bodied sons who can keep their hands off their cell phones long enough to help you move and flatten a few tons of sand and cement in a 4 hour period. This job is the optimal way to flatten the floor, but is better left to the pro's who will be very large men with some serious equipment.

Re: Floor leveling


You have two ideas for flattening out your floor. But, the way I see it, the real problem here is that neither one of them is any good. You need a better idea.

You've come to the right place.

What you need to do is investigate the Johnsonite Subfloor Leveler System:


Basically, this system consists of a family of hard rubber wedges, each 4 feet long and tapering from one thickness on one side to a different thickness on the other side, like this:

Notice how the green sheet rubber flooring tapers every so gradually upward so that it's flush with the grey speckled flooring? That's accomplished by the 4 foot long rubber wedge that's zero thickness on one side and 1/8 of an inch thick on the other.

You can buy these strips in 0 to 1/4 inch thickness, and I figure that's about what you'd need to go up 2 inches over 9 feet. In your case, you'd need a total of 9 X 19 / 4 = 43 pieces of 0 - 1/4" rubber. The rest could be filled in with any 1/4 inch thick material, such as plywood or Hardibacker board or even particle board or masonite.

And, basically you just glue the strips down with any flooring adhesive.

Johnsonite is probably the biggest name in synthetic rubber flooring. You can order their products from any carpet or flooring retailer. It'll be more expensive than pressure treated sleepers, but I expect you'd get a sturdier floor.

Re: Floor leveling

Buy 8 @ 10 foot 2x4's. Cut them to the exact length for the room. Using a chalkline, mark a tapering line from 3/4" at one end to 2 3/4" at the other. See how the difference in width from end to end becomes 2"?. You can't go to zero with sleepers.If you cut the line carefully you now have 16 identical tapered sleepers. Apply a bead of construction adhesive suitable for pressure-treated wood under each sleeper, spacing them 16" O.C. Fasten them down with Tapcons and/or a Ramset/Hilti driver. This will work if you can spare the extra 3/4" at the high side.
Ideally the space would have a finish floor at the exact same height as in the rest of the rooms. So a 2x4 ripped lengthwise may not be enough height, but I'm working with the situation as described.

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