Moisture in Matt’s Apartment: Plumbing Problems Lead to Pests

Cracks behind bathroom fixtures and missing caulk can create open passageways for pests into your home.

Cracks behind bathroom fixtures and missing caulk can create open passageways for pests into your home.

By: Marcia Anderson

When I went to use the bathroom in my son’s city university apartment, I was greeted by more than I bargained for. I flicked on the light switch and black creatures moved from the sink and bath tub into cracks behind the fixtures. After a bit of sleuthing I discovered caulk missing from around the bathtub and sink – perfect places for both moisture and pests, such as cockroaches, to accumulate. It was not as bad as Joe’s Apartment ‘(1996, MTV Films) but I was just as creeped out.

Most people are unaware of the association between plumbing problems and pests, but the fact is that the two are intertwined. Bugs and rodents are attracted to water. If you have a leak or a place where moisture is allowed to accumulate in your apartment, house or school, it will attract pests. To get rid of pests and keep them from coming back, you have to deprive them of everything they need to survive: food, water, shelter, and ways to get around.

If you have a leaky faucet or other water source along with a tiny hole in your wall, pests will make themselves at home, in your home. Pests, such as cockroaches, may also move between neighboring apartments along plumbing and electrical ducts. Seal around these entry points to keep them out.

Once inside, cockroaches like to hide in cracks and crevices where it’s dark and warm and there’s food and water nearby. The single most important factor in determining cockroach survival is the availability of water. Moisture makes your bathroom and kitchen ideal places for finding whatever’s bugging you. Water left in the sink after washing dishes or in the bathtub after a shower provides moisture for cockroaches. These sources are eliminated by drying out sinks and bathtubs after use. You can help eliminate pests by getting rid of other sources of moisture, like piles of damp towels or laundry that attract silverfish. Use your bathroom window or fan to vent shower steam to prevent mildew and mold.  Report or fix vents that aren’t drawing air out. 

Another favorite place for cockroaches to hide is in your bottom kitchen cabinets. They are a potential pest nirvana with trash, moisture, clutter and dark hiding places. Another common source of moisture in the kitchen is condensation under the refrigerator. Place a pan under the appliance to collect water and empty it frequently.

Pet water dishes and aquariums are also sources of moisture. Empty water dishes at night when cockroaches are foraging but your pet is asleep. Aquariums should have tight fitting lids or screens to prevent cockroach entry. And be careful not to over-water indoor plants because the excess water is available to cockroaches.

In storage areas keep cardboard boxes and even plastic bins off the floor and on a wire rack or shelf. Be especially rigorous on concrete floors as moisture forms between the floor surface and the box bottom attracting silverfish and cockroaches. They will start by eating the box bottom, and quickly make their way into the inside of your boxes, destroying priceless photographs, documents and clothing. Another reason to use storage racks is for easier pest inspections. With boxes off the floor, you can quickly spot mouse droppings and evidence of other unwanted critters.

Be Pest Wise! Regular maintenance such as fixing leaks, sealing holes and cracks, and sanitation are key components of a smart, sensible and sustainable pest management program. Recognizing the value of pest prevention is an important first step. See EPA’s webpage on controlling pests in your home, school, or business for more information.


About the Author: Marcia is with EPA’s Center of Expertise for School IPM in Dallas, Texas. She holds a PhD in Environmental Management from Montclair State University along with degrees in Biology, Environmental Design, Landscape Architecture, and Instruction and Curriculum. Marcia was formerly with the EPA Region 2 Pesticides Program and has been a professor of Earth and Environmental Studies, Geology, and Oceanography at several universities.

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