Tuesday, June 19, 2007
Back when our first cockroach of the year showed up, my husband said he wondered how it got inside. Since I've read roaches can squeeze in through very small spaces and live in tiny places, I never thought much about it but the truth is that there aren't any gaps in the floor boards, ceiling, or holes in the walls through which insects could pass if they were living in such places. All of our windows and sliding doors have screens so, unless the roaches are strong enough to slide one open and shut or small enough to squeeze through the most infinitesimal gap between screen and frame, there was no way I could think of that they could get in.
While considering when to take down and clean the kitchen exhaust fan, it suddenly occurred to me that it represented a prime orifice through which any sort of small creature or insect could enter the apartment. In fact, at some point a long time ago, a small lizard actually was crawling on the wall in our kitchen and that was a serious mystery until now. The fan has no screen of any sort behind it but rather a hood which is open to the outside. Anything that is 6 inches or smaller can easily crawl or fly up into the vent and enter through the fan blades when the fan is off.
Since the fan opens into the kitchen and is designed to suck out natural gas fumes as well as cooking odors, anything which is attracted to the smell of food will be drawn to the vent. You can't see behind the fan in the picture above but the hood leading to the outside is absolutely coated with thick, greasy crud resembling cakes of soot. It can't be cleaned by me, of course, as it's an external vent which is very high up on the wall outside and has 20 years of gunk on it. I imagine there is something in there to attract the discerning roach should he find his way up there (the males can fly). I also wonder now if mosquitoes and moths may have been getting in this way.
Since this is the biggest opening which is unscreened that leads outside, I decided it'd be a good idea to do something to screen it off in some fashion so I picked up a sheet of batting designed to filter oven exhaust fans and attached it to the fan's frame. I attached the sheet to the fan pulling it as tightly as possible but the fan is nearly flush with the frame and when it was turned on and started sucking air out, the blade caught on the batting and tore it up.
My husband suggested that it'd work if we found a way to raise the filter higher off the frame and while buying another sheet of batting, I noticed the type of extra long sponges (they're about 1 foot long and about 5 inches wide) that you cut to size. I figured that I could buy one of these, cut it up and use it to raise the filter from the frame.
If you look at the picture above, you can see where I attached the sponge pieces to the frame with double-sided tape (the sponges are white but can still be distinguished from the fan's frame). I then stretched the filter as tight as I could over the frame and taped it down on all sides. Since the filter material is flexible, it still gets sucked inward to a small extent but it's still far enough from the blades not to get hacked up.
The filter should keep the fan from getting filthy with dust but more than that I'm hoping that it keeps anything that is outside from crawling in. It'll be interesting to see if we see no more cockroaches this year after putting on this filter or if they're finding their way in via some other route.