When the HVAC tech came in & did the inspection on our furnace, she also diagnosed the ductwork. She told us she had noticed a couple of cracks along the seams of the ductwork. She wanted to call a team of professional ductwork cleaners & have them inspect the entire ductwork plan & see if it needed repaired or updated? If it was able to be repaired, they would repair the ductwork, then clean & sanitize it. I sad about what it was going to cost if I needed to update the ductwork. I knew it had to be pretty old. The ductwork was already in the house when all of us obtained it, nearly fifteen years earlier. I agreed to have the ductwork professionals come to the house & inspect the ductwork. When they arrived, I asked them why the ductwork was so important. They explained that the ductwork was like a major highway. It is how the heating & a/c is directed through the entire house. When there was a crack or hole anywhere in the ductwork, there was a loss of heat or A/C coming through that hole. We would be wasting energy since all of us didn’t have respected airflow, & there was a loss of energy/HVAC. I didn’t want to be losing heat or a/c, although I knew it would be fancy to update the ductwork. I held my breath as the inspection was done. Luckily, all they had to do was seal the ductwork, & then they cleaned & sanitized it. Our ductwork was good for at least another 2 years.