Hi...I wasn't sure where to ask this so here goes....I live in a 50+ year old building that is undergoing repairs on the balconies....removing old concret by jack hammer and it is definetly shaking things up in our appartments. They are exposing the rebar. My question is...what is it doing to the structural integrity of the building? I live in Toronto,Canada and sure we don't have a big fear of earthquakes or other building damaging natural hazzards...but could the building collapse? I don't know...an old building....stress....etc....any comments or ideas?