Spiders: Why They Are Really in Your House

Spiders set up where the food is, so webs concentrated around your door frames, eaves and exterior lights mean there is a steady insect supply there. Reducing the insects and removing the web anchor points does more than spraying the spiders themselves.

Following the food

Spiders do not eat your house or your food. They eat other insects. A house with heavy insect activity around the foundation and lighting is running a buffet, and the spider population simply reflects that. This is why spider numbers track insect numbers with a short lag.

The lighting connection

Exterior lights draw insects, insects draw spiders, and the door you use most is usually the best-lit. Switching to warm-toned or yellow bulbs draws noticeably fewer insects, which is one of the cheapest changes available and one almost nobody makes.

The two worth identifying

Most spiders here are harmless and useful. The two that matter medically are the brown recluse, with a violin shape behind the eyes and a habit of hiding in undisturbed storage, and the black widow, glossy black with a red hourglass underneath, found in woodpiles, meter boxes and under decks. Both avoid people and bites usually happen when the spider is pressed against skin.

What actually reduces them

• Perimeter treatment to cut the insect food supply
• Web sweep across eaves, soffits and door frames on every visit
• Warm-toned exterior bulbs
• Clearing clutter in garages and storage, which is recluse harborage
• Moving woodpiles away from the house

See our perimeter pest control program