Red house spiders are not poisonous. Spider fangs are too weak or small to puncture human skin, but when they do, the venom is harmless and at most may cause redness, slight swelling and itching.
North American red house spiders are often confused with red-back spiders, which are venomous, but live only in Australia. North American red house spiders are rusty in color and similar in size to a dime. Dark, undisturbed indoor places are favored for spinning webs, such as under eaves, along baseboards and in door frames. Homeowners should clean out clutter such as paper bags, boxes and newspapers to prevent nesting and minimize bites.