In my current house we used 16-18" deep floor trusses over the basement. On top of that we used 3/4" plywood. Carpet was installed directly to the plywood and in areas where we laid travertine we put in a cement backerboard on top of the plywood.

Our house is in escrow and we will be building another home with a basement. I would like to have less deflection in the next home and more noise insulation. It find it annoying that when walking across the floor it makes things rattle (not so much that you can feel it but things on the floor or connected to it will rattle). It also sounds hollow. When I am in the basement I can hear basically everything that goes on upstairs.

I am looking for a better flooring system. I have looked at Insul-Deck and other ICF style forms used to pour a concrete slab over a basement. But it is quite expensive. My neighbor used this and it's nice. It feels like a solid slab beneath your feet.

I think a less expensive option would be put in a layer of cement (Gypcrete style) over a traditional trussed floor. I imagine the trusses would need to be engineered for this and I am not sure how the deflection and noise would respond. You could also hang the drywall below this system with resilient channels to reduce noise, and add insulation either batt or foam.

Does anyone have experience with this or comments/suggestions?