I'd really like to suppress the sound. Doing that well is non-standard, and thus expensive. There are so many obvious fixes that introduce other problems. Text

I'd really like to suppress the sound. Doing that well is non-standard, and thus expensive. There are so many obvious fixes that introduce other problems. Textured surfaces like carpet and popcorn ceilings get filthy disgusting. Wooden walls and ceilings are a fire hazard. I think white silicone rubber would be an excellent surface material. It won't burn, nothing eats it, it won't rot, it can be scrubbed with bleach or detergent, and it can have the right sort of softness for absorbing sound. It could work as floor tiles or wall panels, with a smooth exposed surface and a waffle-like backing to grant it some additional squishyness. For the ceiling it could even be like stalactites, perhaps 4" diameter and 20" length, to better absorb the sound.