Pest Library
Window wells: the Salt Lake basement's pest doorway
For a Salt Lake basement, the window well is the front door for pests. Here's what lives in them, and the simple fixes that close the door.
By Alvin Fairbanks, Pest Control Guides Editor
Updated September 2026 4 min read
Short answer
Window wells collect leaves, moisture and insects, which makes them ideal for spiders, including black widows, earwigs, crickets and the occasional mouse. Keep wells clear of debris, fix drainage so they don't hold water, add clear covers and have the wells treated as part of a regular visit. Always wear gloves when reaching into a well.
Why wells attract pests
A window well is a small, sheltered pit next to the foundation. Leaves blow in and rot, moisture collects, and insects follow. Spiders move in to hunt them, and the basement window a few inches away is an easy next step.
What lives in them
Different pests use wells for different reasons.
- Black widows and funnel weaver spiders in the corners
- Earwigs, crickets and pill bugs under wet leaves
- Mice looking for a way into the basement
- Occasional toads, voles and other small animals that fall in
Window wells matter more in Salt Lake City than in many places, because the median home was built in 1965 and about a quarter of homes predate 1940, many with basements. USU Extension notes hobo spiders are found in Utah homes most often from August through October, and that the black widow is the major spider of medical concern in Utah. Both show up in window wells, which makes wells the first thing to clean and treat before fall.
Covers and drainage
Clear polycarbonate covers keep leaves and animals out while letting light in. Make sure the well has a gravel bottom that drains, and that downspouts and sprinklers aren't dumping water into it. A dry well supports far fewer pests.
Cleaning a well safely
Wear thick gloves, because black widows favor window wells. Use a long-handled tool to pull out leaves and debris, knock down webs and bag the waste. Check the window frame and seals while you're there.
When to treat
Wells are treated on every good residential visit, and they get extra attention in late summer ahead of the fall spider season. If webs come back within days of cleaning, spiders are breeding nearby and the well and foundation need treatment.
Sources
Yes. They keep leaves and animals out and help the well stay dry.
Yes, window wells are one of their favorite spots. Wear gloves.
Wet leaves in window wells shelter earwigs right next to basement windows.
At least in spring and fall, and after storms that blow leaves in.
Yes, through gaps around the window frame or foundation.
Yes, on every residential visit, with extra attention before fall.
Keep reading
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Read the articleTalk to us
Wells full of webs?
Call now to get the wells cleared and treated before fall.
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