Said It Here

How to stop low-frequency compressor noise coming through walls and floors

Standard wall foam and rubber pads only block high-frequency sounds, leaving low-frequency rumbles to travel directly through structural framing and concrete slabs. This vibration transmission makes it impossible to lower decibel levels or stop the noise from penetrating living spaces, which is why basic soundproofing fails.

What people tried

Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.

  1. 1
    Installing sound absorbing foam all over the walls
  2. 2
    placing rubber or cork pads between the housing and concrete slab
  3. 3
    installing neoprene washers or sheets between mounting brackets and the housing

In their words

Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.

r/homeowners1 person · September 2026

Neighbor’s AC unit is transmitting a vibration/noise into my house.source ↗

Tried putting those square rubber/cork pads between the housing and concrete slab…no change.source ↗

antiramie · r/homeowners · 1 upvotes
r/HomeImprovement1 person · September 2026

i've added sound absorbing foam all over the walls and it has helped but a loud rumble still makes it way out. it's around 65 decibels right now with the foam & doors closed..hoping to bring it down closer to 50.source ↗

luludrone · r/HomeImprovement

Where this came up

People with this problem also raised