Laundry room floor

The laundry room is on the second floor, near our bedroom. The washer and dryer are Bosch Next 500 models, which are high-speed front-loaders. The word is that they can vibrate a lot, although you can minimize that with proper levelling. So we wanted a floor that would dampen vibration and absorb noise.



The structure of the laundry room turns out to be ideal, and I still wonder whether MSI did this deliberately. The floor of this 5x6 room is supported by 6 engineered joists, which are connected only to the band joist at the edge of the house. That is, there's no direct connection between the second floor structure and the first floor ceiling, they're decoupled. We added some 2x6 cross-bracing for good measure.

The actual floor is 3/4" plywood with 1/2" durock. The tile is set on a waterproof membrane, so we don't need a pan under the washer to catch water: in the unlikely case of failure, the little water the washer holds can just leak onto the floor. (Washer pan/drains are problematic because they aren't allowed to drain into the sewer.)

Under the floor is 4" of rock wool for noise control, plus rigid insulation around the exterior. The laundry machines will rest on 1/2" compliant grommets.

I hope this makes the laundry room acceptably quiet, because I don't know what more we could do.