To be LEED certified, the ductwork used to ventilate 40 bathrooms in the newly constructed five-story building had to demonstrate a total leakage rate below 250 CFM. With first test results showing 900+ CFM, it wasn’t even close. Not only was proper IAQ and bragging rights to another energy-efficient building at stake, but so were thousands of dollars in federal rebate dollars that the Cambridge Housing Authority (CHA) planned on receiving through LEED certification.