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.