Super Soundproofing Community Forum

Soundproofing Forum Topics => Soundproofing your Condo, Townhouse or Bed & Breakfast => Topic started by: shaney on September 25, 2007, 08:42:09 PM

Title: impact noise from BELOW?
Post by: shaney on September 25, 2007, 08:42:09 PM
I co-own a loft apartment with a concrete floor and in late February/ early March of this year we started to hear footfall and bangs from below and noticed an increase in floor vibration from outside traffic too.  There's not much of an airborne noise problem - it seems to be impact/structural. 
It turns out that the owner of the apartment beneath had a severe condensation and mold problem which his tenants began to notice around the same time. The only changes he had made in the apartment beneath ours, were to install vents to help with this, and he eventually agreed after much negotiation to cover these temporarily to rule them out as having anything to do with the impact noise.
They've been ruled out now, and I'm just wondering if anyone has any ideas on what else might be causing this impact/structural noise problem.

The ceiling/floor construction is: plasterboard ceiling, resilient channels, mineral wool of some kind, and a concrete slab floor. I don't think vapour barrier was included - trying to get confirmation of this from the developer's construction manager, and also a few more answers, like whether the floors are built into the vertical brick or butted to it. The guy is not very forthcoming.
We've laid acoustic underlay on top of the concrete floor beneath thick new carpet in one room but this has not helped.
We have realised that doors banging in the stairway, even on the ground floor ( we are 3 floors up and share a stairway with 5 other apartments ) and footfall noise on the stairs is some of what we're hearing, in addition to internal impact noise in the apartment beneath, but it all seems to be coming through the floor.

I have one theory which may or may not be on the right track - could the wetness in the drywall in the apartment beneath have ruined the insulation in the ceiling?
Does ceiling insulation usually stop impact noise transfer between floors?

If anyone has ever encountered a similar issue or can offer any enlightenment we'd be very grateful.