I am amazed at how often I see plugged dryer vents. The lint/dust that plugs these vents represents a significant fire hazard and should be maintained free of debris. This is something that the homeowner/handyman can do. Everyone's use of dryers and the types of clothing they dry is different, so determining how often to clean them requires some cleaning "history". Clean them as often as necessary. If they are clean and the flap works properly and isn't stuck open they are most likely fine. The line to the vent cap should also be maintained clean---but this will get us into another blog. There are specific "types" of vent caps that can contribute to frequent clogging. They should NOT be screened. Screens and grille type covers will clog the vent cap much quicker. Another problem can be location---how easy is it to get to. Vent caps at the steep roof of a three story townhouse will not be accessible to the average homeowner (many inspectors won't even go on these roofs) and should either be relocated to more accessible location or some sort of maintenance plan will need to be set up with qualified maintenance persons to keep the caps clean. I also don't like the louvered type of vent caps---the little louvers bend due to heat and then don't open all the way which leads to clogging. So keep those dryer vents clean!
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Patricia AUlson/Hampton NH Real Estate
The dryer vent on the roof really wins for best example of a clogged vent. Great first blog.
Pat---I haven't revisited this post since Bob just brought it back to life---today I am a lot better at commenting back to people's comments :) In fact I have an upcoming post about that.
Bob, thanks for digging into my sordid past :)