Hi,
Just purchased a condo and moved in to notice that every time a subway passes underground I feel and hear it. I am on the 6th floor and it is not too bad (which is why I did not notice it when I viewed the apartment but I can definitely feel the vibration and hear the subway when the TV is not on. I am planning to do a full renovation for the apartment so is there anything I can put under engineered hardwood floors to reduce the vibration (which concerns me more than the sound)? I am also planning to put in soundproof double pane windows to reduce general city noises - will that help with the vibration as well?