I had a floor about 5/8 out of flat with a hump in the middle. I tried using the self-leveling compound you can buy but it didn't work well at all. It doesn't self level, it creates a convex surface. So now I have 4 humps in my floor.The self-leveling compound is very hard to screed because of the viscosity, so I got some compound that you level yourself.I'm thinking of laying pieces of shingles on the floor as level indicators and then pouring the non-leveling compound between them, trying to screed between the shingles and level it with a trowel. Is this a good approach? It is a 12x14 room.Would it be better to use grout instead of the leveling compound so I have more time to screed it? The leveling stuff sets up so fast.
This may help you: use a thick underlayment like cork or foam that can help with the sound.
A few things need to be cleared up. The self leveler, if done properly should have worked. You probably didnt mix it thin enough, or you did not use enough and tried to trowel it around.. The product , like water, seeks its own level. Also, a 5/8 hump in the floor may have been within tolerance, especially in a room that large. You also should not be putting that floor on a raw concrete sub floor anyway. I am not sure of your budget, but it really should have some sort of sleeper system under it. The concrete has to much moisture, and the engineered floor is still a fibre product, which means its going to suck the moisture in. Go to the manufacturers site. Lastly dont use mortar. Sand base will turn to powder the more foot traffic it has.
