Greenhills School in Ann Arbor Michigan has acheived a LEED Gold certification. The Bard Q-Tec 2 stage geothermal heat pumps were used in many of the classrooms. These units are equipped with internal energy recovery ventilation and controlled by CO2 sensors. These units met the LEED requirement of an operating sound level of 45DB's in the classroom. These units were all duct free, which means the sound levels of the Bard product is very low.