As a Seattle Home Inspector, a very common issue I report on has to do with exhaust fan vent caps. For such a simple thing, there can be lots of things wrong with them. Fortunately, no matter what the problem is, the repair is not likely to be a deal breaker. They can be missing, wrong size, wrong type, damaged, screens clogged, screens present, screens missing (although I would argue this is rarely a “defect”), missing back draft dampers, dampers damaged, dampers stuck open, dampers stuck closed, louvers missing, louvers damaged, louvers warped, too close to the ground, not accessible----I think you get the idea. Today I am going to discuss metal, round, louver type vent caps that have absolutely no business being used on mechanical exhaust fans. The following picture is an excellent example of what happens when one of these caps is used on an exhaust fan. In a relatively short period of time the louvers (and sometimes they have screens behind the louvers too) become clogged with lint or they get painted over on the outside. How is this cap going to get cleaned? Well it is not, and thus the exhaust fan is not going to do its job----and thus we have another possible “conducive condition.” A conducive condition is defined as just about anything that when not functioning properly can contribute to moisture issues in the home. Charles Buell
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Charles - Few, including most builders and subcontractors, realize the importance of vent covers and the potential for significant problems. This weekend I'm visiting a friend to look for an alternative route for their clothes dryer vent. It seems the builder vented the dryer through the roof causing problems with their dryer and presenting a potential fire hazard.
Another good tip, Charles!
Debi
Charles....you know you don't give it much thought until you need to use it and then, you want it to work as represented. If it doesn't, it bothers you....To me this is one of those things........Small, but necessary..
Thank you Charles the Inspector
This post has been brought to you courtesy of home inspector extraordinaire Charles Buell, and with apologies to the Jefferson Airplane!
I have been pointing out vents at most every home. Spreading the word will hopefully change that.
I can tell you first hand that clothes dry faster when the vent is unclogged.
You always have a great play on words Charles...
Have you noticed any difference from those new servers yet?
Paul
John, clothes dryer vent caps are especially problematic----I often find dryer vents on 3 story roofs with pitches too steep to walk by the average bear.
Debi, thanks.
Richie, and sometimes just because you can hear them running does not mean they are doing anything more than making noise.
Craig, the Jefferson Airplane are always deserving of compliments :)
Dennis, perhaps in time.
Kate, ain't that the truth.
Paul, not much yet----of course Bob announced a change to tonight from last night.
Hey, by the way, are you seeing less proxy errors?
Hi Charles, This makes a lot of sense. I can imagine people doing what you said, painting without cleaning them and thus rendering them like a solid hard mass. I haven't seen these used here in SD very often. I see more of the hood type with the damper. Or at least a hood where there used to be a damper, LOL.
That looks like the vent on the side of the cotton candy machine at the local carnival. You can't fool me.
That's a candy-ucive condition.
Charles - Yuck! And how inefficient is that now. Conducive condition is right.
Charles, Just shows how easy these vent can clog up and cause issues. Good post
Kate, not really
William, I would say the vast majority of the ones that I see are of the damper type too, but every once in a while.....
Jay, will you do a taste test for me?
Susan, it is important to not only use the exhaust fans but to also make sure they are doing something :)
Donald, yes very easy.
Charlie,
I waded in tonight, first time in 48 hours, to check it out. Got one proxy but generally working better.
The worst part is when seagulls attack!!! They can really clog up the works!
Steve, you need to keep waddling in----that is what Quackster says.
Donald----dang seagulls anyway :) Worse than Nutsy.
Charlee.
Good one. That louver is a mess for sure! Now I am going to take a closer look at them.
Charles, a good tip to ensure that we check out the vents in our homes. Thanks,
Lloyd, let us know what you find :)
Rebecca, I am surprised no businesses have sprung up dedicated solely to taking care of these vents and ducts.
It is amazing the kind of common sense things that people miss.
Inspect, inspect, inspect. It is always so important that my buyers are using professionals to be looking for these things. I learn something new on almost every inspection.