Ducting is a the neglected stepchild of the residential mechanical world. Contractors are trained to sell, install and maintain equipment, ducting is left to care for itself. My HVAC guru George Gary tells me there is little or no profit for HVAC contractors in duct design, sealing, repair or maintenance.
I find lots of disconnected, dirty, unsealed, poorly insulated and poorly designed duct systems. Energy loss in the systems I inspect averages around 25%. Ducts often draw (“entrain” is the industry term) dirt, odor and contaminants into conditioned air: the air you breathe.
The costs of poor ducting are higher energy costs, reduced comfort and potential health problems.
Too bad most homeowners won’t pay to have their ducting fixed. The return (pun intended) is a lot better than most investments