We are in a new build conversion (old building new renovation) the ceiling of our flat is new and not an original part of building and the walls are plasterboard. We are being plagued by walking and thumping sounds from the apartment upstairs (no tv/music noises) the apartment is 9 months since completion, and the noise has got progressively worse in the last 3-4 months. We do not get noise through the walls or next door just through the ceiling. I am of the idea that the apartments have floating floors but could be wrong. We have contacted the builder/developer who are in the process of coming round and we have informed upstairs (to be honest I do not think it is anything to do with them and how they move around the flat). Firstly I'd like to know what sort of thing I should be questioning the builder on and any terminology for what type of issue I actually have and/or remedial action advised. Secondly failing potential action by them and nhbc what are potential sound proofing options for this type of noise issue. Thanks