I have always been intrigued by the giant house spider, especially when I see one darting across my floor at high speed. If you’ve ever encountered a large, fast-moving spider in your home, you might have been startled or even a little worried. Many people mistake them for dangerous species, but the truth is, they are completely harmless to humans and can actually be beneficial.
In this article, I’ll share everything I’ve learned about the giant house spider, including how to identify it, its behavior, bite risk, and whether you should remove it from your home or let it stay.
What is a Giant House Spider?
The giant house spider (Eratigena atrica) is one of the largest spiders commonly found indoors. They are part of the Agelenidae family, also known as funnel-web spiders (not to be confused with the dangerous Australian funnel-web spider).
Quick Facts About the Giant House Spider
- Scientific Name: Eratigena atrica
- Size: Leg span can reach 4 inches (10 cm)
- Color: Brown, dark brown, or tan with lighter markings
- Speed: One of the fastest spiders, running up to 1.73 feet per second
- Habitat: Basements, sheds, garages, and dark corners of homes
- Venom: Mild venom, but not dangerous to humans
Giant House Spider Identification
If you’ve ever spotted a large spider in your house, you may have wondered whether it was a giant house spider or a more dangerous species. Here are some key features to look for:
Physical Characteristics
- Large body and long legs
- Dark brown or tan coloration with lighter markings
- Distinctive chevron-shaped patterns on the abdomen
- Legs are covered with fine hairs but not overly fuzzy
- Two large fangs (chelicerae), but they rarely bite humans
Difference Between a Giant House Spider and a Hobo Spider
The hobo spider (Eratigena agrestis) is another member of the funnel-web family, and it is often confused with the giant house spider. Here’s how to tell them apart:
| Feature | Giant House Spider (Eratigena atrica) | Hobo Spider (Eratigena agrestis) |
|---|---|---|
| Size | Up to 4 inches leg span | Smaller, 1-2 inches leg span |
| Color | Dark brown with lighter markings | Uniform brown with no patterns |
| Web Type | Funnel-shaped webs in corners | Funnel-shaped webs at ground level |
| Bite Risk | Harmless to humans | Rarely bites but can cause mild irritation |
If you’re unsure whether you’ve found a hobo spider or a giant house spider, giant house spiders are much larger and faster.
Where Do Giant House Spiders Live?
Indoor Habitat
Giant house spiders love dark, quiet places where they can build their webs. In my home, I have found them in:
- Basements
- Garages
- Attics
- Sheds
- Behind furniture or in closets
They avoid human activity and prefer undisturbed areas.
Outdoor Habitat
Outside, giant house spiders are often found in:
- Wood piles
- Garden sheds
- Under rocks and logs
- Near entryways
Unlike some spiders that prefer warmth, giant house spiders can tolerate colder temperatures, making them common in Europe and North America.
Giant House Spider Behavior
Why Are They So Fast?
One of the most notable things about giant house spiders is their incredible speed. They are among the fastest spiders in the world, reaching speeds of up to 1.73 feet per second.
They rely on speed to escape predators rather than biting for defense. If you try to catch one, you’ll notice how quickly they dart away and hide in cracks or corners.
Do Giant House Spiders Build Webs?
Yes! Unlike jumping spiders or wolf spiders, which hunt actively, giant house spiders build funnel-shaped webs. These webs act as a hiding place and a trap for insects.
They sit inside the funnel and wait for prey to enter before rushing out to capture it.
What Do Giant House Spiders Eat?
Like most house spiders, giant house spiders are natural pest controllers. They feed on insects, including:
- Flies
- Mosquitoes
- Cockroaches
- Moths
- Ants
If you leave a giant house spider in your basement, it will likely help keep other pests under control.
Are Giant House Spiders Dangerous?
Do They Bite?
Yes, but only if provoked. A giant house spider is not aggressive and will try to run away rather than bite.
Giant House Spider Bite Symptoms
If bitten (which is very rare), symptoms include:
- Mild pain similar to a bee sting
- Slight redness or swelling
- No long-term effects
Unlike black widows or brown recluse spiders, giant house spider venom is not dangerous to humans.
How to Prevent Giant House Spiders in Your Home
If you don’t want giant house spiders in your home, here are some effective prevention tips:
- Seal entry points – Close cracks around doors, windows, and vents.
- Reduce clutter – Spiders love hiding behind boxes and furniture.
- Vacuum regularly – Removing cobwebs discourages them from staying.
- Use natural deterrents – Spiders dislike peppermint oil, citrus, and vinegar.
- Limit outdoor lighting – Lights attract insects, which in turn attract spiders.
Should You Kill a Giant House Spider?
Why You Should Let It Stay
Although they may look scary, giant house spiders are beneficial. They keep insect populations under control and are completely harmless.
If You Need to Remove It
If you don’t want a giant house spider in your home, here’s what I recommend:
- Trap it in a glass using a piece of paper.
- Gently carry it outside and release it.
- Avoid killing it, as it helps reduce pests in your home.
Conclusion
The giant house spider is one of the largest and fastest spiders you may find in your home. Despite their intimidating size, they are harmless and beneficial.
