Ventilation
Fan power and pressure loss increases as the flow rate of a mechanical ventilation unit increases, even when it is increased to overcome leakage in the ductwork system to maintain the hygienic flowrate in the rooms. The harder the fan has to work, the more sound power it will produce.
Therefore, even high-performance mechanical ventilation units will produce more sound than is necessary when they are connected to leaky ductwork systems, but not when they are connected to Ubbink’s Aerfoam and Air Excellent, which are class D/ATC 2 airtight even when installed.