| To be honest, a thick rubber mat is probably not your best, or most cost-effective, method for this. First, the rubber (particularly assuming it's a hard rubber that you would want to stand on) will still have a certain amount of resonance, and you won't have any decoupling between it and the wooden floor. And this will also not help you with the flanking noise.
Again, the two important things to understand with all of this are decoupling and flanking noise.
What's underneath the wood floor? Is it hollow, with studs underneath? Then what's underneath that -- dirt? concrete?
If it's a hollow floor with studs underneath, I'd fill those hollow spaces between the studs. If it's just dirt underneath, I'd fill the space underneath the floor with sand (drill holes in the wood floor if needs be). It there's concrete underneath and you don't need to worry about moisture collecting in the fill material, you might fill it with fiberglass insulation (if you can) or blown in insulation.
From there, you can either add a floating floor, or add some decoupled mass to the floor, such as additional layers of plywood, (or a sandwich of multiple layers of drywall and plywood or chipboard), with Green Glue in between the layers.
There are numerous ways to float a floor. You can float them on acoustic isolators like sorbethane pucks, or you can use a layer of fiberglass insulation between the floating floor and subfloor. Then you need to make sure that the floating floor surface does not come into contact with the walls, and seal the gaps with mastic, acoustic caulk or whatever.
I guess it depends on how much isolation you really want/need . . . but I would expect that even adding a layer or two of additional plywood or chipboard with a layer of Green Glue between the sheets of wood (for every layer you add) will give you more isolation than using a thick layer of hard rubber matt on the floor. |