How to get rid of spiders in your house, basement and garage

Step by step: how to get rid of spiders in your house, basement and garage

Safety first. Wear gloves and long sleeves when you clear boxes, firewood or storage in a garage, basement or crawl space, where black widows and, in some states, brown recluse spiders hide. If you are bitten by a spider you think is dangerous, stay calm and get medical advice; bring the spider if you can do so safely.

1. 1

   Vacuum spiders, webs and egg sacs

   Go room by room with the hose: ceiling corners, behind furniture, window frames, under beds and along baseboards. Vacuum the egg sacs too (small round silk balls), since each one can hatch many new spiders. Spiders’ soft bodies usually do not survive the trip through the hose.

2. 2

   Knock down outdoor webs

   Use a cobweb duster or a strong hose spray on eaves, porch ceilings, window frames and around outdoor lights. Repeat weekly for a few weeks; webs that keep coming back show you where spiders are living.

3. 3

   Clear clutter in the basement and garage

   Move boxes off the floor and away from walls. Pack stored items into lidded plastic bins or seal cardboard boxes with tape so spiders cannot move in. Throw out old paper, rags and cardboard stacks, which also hide the insects spiders eat.

4. 4

   Set flat glue traps along baseboards

   Place flat glue traps in corners, along wall and floor edges, behind furniture and under stairs, out of reach of children and pets. Check them weekly. The ones that catch the most show where to focus your cleaning.

5. 5

   Seal cracks and gaps

   Caulk gaps around window frames, pipes, cable lines and cracks in the foundation. Add door sweeps and weather stripping, and repair torn window and door screens. Good screens keep out the insects spiders feed on as well as the spiders.

6. 6

   Change the outdoor lighting

   Outdoor lights draw insects, and insects draw spiders. Turn porch lights off when not needed, use yellow bulbs, and close blinds at night so indoor light does not pull insects to the windows.

7. 7

   Clean up around the foundation

   Keep a strip next to the house clear of leaf litter, woodpiles, trash and thick plants. Trim shrubs and vines so they do not touch the walls, which gives spiders a bridge inside.

8. 8

   Catch and release single spiders

   For a spider in the open, place a clear jar over it, slide a stiff card underneath and carry it outside. Most house spiders are harmless and eat flies and other pests, so a few outside the house are useful.

Which spider home remedies actually work?

Vacuuming, sealing, decluttering and sticky traps are the home remedies that work. The University of California IPM program says to focus on removing webs and hiding places, and that pesticides are not generally needed. Sprays are temporary unless you also keep the house clean, and crushing or vacuuming a spider is just as effective and much less toxic.

How to get rid of spiders in a basement

Basements collect spiders because they are dark, undisturbed and full of storage, so the fix is to make them less of all three. University of Kentucky entomologists describe spiders in basements, garages and crawl spaces along joists, sills and rafters and under rolled insulation, and recommend reducing clutter, storing seldom-used items in plastic containers and using many flat glue traps along wall and floor junctions.

• Vacuum the ceiling joists, window wells and the top of the foundation wall.
• Lift storage onto shelves away from the walls and use lidded bins.
• Run a dehumidifier if the basement is damp, which cuts the insects spiders hunt.
• Shake out shoes, gloves and clothing kept in the basement or garage before wearing them.
• Pull beds away from walls and remove bed skirts that touch the floor if you find recluse spiders.

When is a spider dangerous, and when should you call a pro?

Most house spiders are harmless; the two to know are black widows and recluse spiders. An adult female black widow is shiny black with a red hourglass under the abdomen and hangs in a messy web in dry, undisturbed places like woodpiles and garages. Brown recluse spiders live in the south central and Midwestern US and have six eyes in pairs rather than eight.

Call a licensed pest control professional if you find recluse spiders regularly, if black widows are nesting where children play, or if glue traps keep filling after a month of cleaning. If you do use a spray yourself, choose one labeled for spiders indoors, follow the label, and keep children and pets out of treated rooms as the EPA advises.

Lots of spiders can also mean lots of insects for them to eat. If you also see flies or gnats, see how to get rid of flies.

Mistakes to avoid

• Spraying insecticide in corners instead of vacuuming, so the egg sacs survive and hatch.
• Storing things in open cardboard boxes on the basement floor against the wall.
• Leaving porch lights on all night, which feeds the spiders on your siding.
• Reaching into woodpiles or storage boxes bare-handed.
• Counting on peppermint oil or plug-in repellers instead of sealing and cleaning.