Just finished a new home and had a blower test done this morning. It came in at 1.72. I did not put in a formal air exchanger. I did however put in a fantec house fan system for the bathrooms There are four at 400cfm that run 10 minutes on every hour and have a 700 cfm booster button for exhaust. I also had the builder put a mechanical damper on the kitchen exhaust hood that opens whenever the hood is running. Given how tight we ar,e any thoughts on whether this is enough exchange air?