"Remember: Your floor should be firm and flat before you install a rigid hard surface product."
Ken's In-Depth Answer:
"Your floor doesn't have to be level. As far as I'm concerned, your room could be built on a hill and have a slope to it. But there are two conditions that are absolutely critical for the installation of any hard surface rigid product. First, the floor has to be flat. Second, the floor has to be firm. Remember: firm and flat - just like you want to be when you leave the gym.
Why is this so? Well, think about it. If you have a hump in the floor, and you put something rigid on top of it, what have you got? You've got a seesaw. It rocks back and forth. On the other hand, if you have a dip in the floor, and you put something on top of it, you have a trampoline. You've got nothing to support it in the middle. Either situation is a recipe for installation failure.
If you've got some minor irregularities, your floor contractor can probably come and patch the floor in order to give you a flat surface. But we have to look at it first and see whether or not the floor is going to sustain an installation of these products.
There is also a second option, which is sheet vinyl, which will pretty much conform to anything."
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