If you have metal ducts in original condition – they leak air. The only question is how much. During our assessment of your home, we carefully examine the ducts by pulling back the insulation wrap in various locations and using a smoke puffer with a visual assessment to determine how bad your ducts are performing. Most of the time you can clearly see the leak points once the wrap has been removed. As part of our audit report, you will receive photos showing the damage. In homes with old metal rigid ducts, the leakage is typically over 40-50%.