Every Breath You Take
Does air duct cleaning really work? The debate rages on. It does seem logical that ducts that are free from dust and dirt would be a positive step in providing cleaner air into your home, however it has been found that there are times that poorly done duct cleaning actually can release more dirt and dust into your home by stirring up the particles that had been securely clinging to the inside of your ducts. I personally think that far and away changing your air filters every couple of months will go a long way toward keeping your air cleaner and your furnace running well.
One thing that is an absolute certainty; keeping your furnace ducts attached to the underside of your floor joists is really important, especially if you have flexible ducts. Current standards require a 4 inch clearance between the bottom of the duct and the soil. More is better.
One reason for this? Rodents are attracted to the warm air that circulates in your ducts and will chew a hole in the duct in order to set up camp or at least to hang out in the cold months. Openings in joints provide an easy entry for rodents too, and the insulation in the ductwork provides nice nesting material. Ducts with rodents in them can become loaded with urine and feces which may contaminate the circulated air that you and your family breathe. A dead rat in a duct can circulate an awful smell throughout your home.
I have done inspections throughout the Bay Area, and there is no city that is immune from rodents in crawlspaces. Keep those crawlspace vents intact! Often cable installers will open a hole in a vent and never bother to seal it up after they run their cable. This hole is an open invitation to any and all rodents.
So the next time you have your furnace serviced or replaced, it is a great idea to have the technician take a look under your home to check those ducts.
See you next time!