Is it lack of insulation or something else?
We live on the first floor of a 6-flat condo built around 1920. All the floors are hardwood. When the neighbors upstairs walk around, it comes through like bass drums in our apartment. Some rooms also very creaky when there is walking upstairs. Some say we have joist problems that might be solved by drilling bolts in to connect the floorboards. Some say there is just no insulation and we would need to open up floors/ ceilings which would be too expensive to make it worth it. One place tried to sell me on spray foam insulation to be sprayed in between our ceilings and the floors above. The noise makes it impossible to sleep. What are the options in terms of getting noise reduction work done? We are not do-it-yourself-ers so we would need to hire someone(s) to do the work. Maybe one for joists and another for insulation? We don't know where to start because is it joists? insulation? both? neither? Who do we trust to do the work?