I discovered completely disconnected ducting in the crawl space at a recent home inspection in Oak Harbor on Whidbey Island. In this particular instance, this ducting was for mechanically ventilating the crawl space area, and had no bearing on the heating system for the home. That said, because it was disconnected, clearly the ventilation system wasn’t functioning as intended or designed and required repair. I frequently discover completely disconnected ducting in crawl space areas for furnaces which significantly compromises the heating efficiency within homes and nicely heats the crawl space areas. Most often, homeowners have no idea because they rarely traverse their crawl space areas.