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Nature

Giant House Spider

What is giant house spider?

· James MacDonald

Key facts

Scientific name *Eratigena atrica*[2]
Body length up to 1.6 cm[2]
Leg span up to 7.5 cm[2]
Speed up to half a metre per second[2]
Web type sheet-like cobwebs[2]
Habitat dark corners of houses, particularly in autumn[2]

The giant house spider is a large house-dwelling spider in the genus *Eratigena*, commonly identified as *Eratigena atrica*. It is known for making sheet-like cobwebs and being found in dark corners of houses, especially in autumn.

Context

The giant house spider is a common sight in homes, especially during autumn when males wander in search of mates. It builds sheet-like cobwebs in dark corners, behind fireplaces, under sofas, and even in baths [2]. Despite its size and speed, it is not aggressive and bites are rare. Some sources treat the giant house spider as a single species, *Eratigena atrica*, while others recognize three separate species: *E. atrica*, *E. duellica*, and *E. saeva* [3]. This spider is often confused with the smaller house spider (*Tegenaria domestica*), but it is the larger cousin [2].

Documented claims

  • It is one of the fastest invertebrates. [2]
  • It is the larger cousin of the house spider (*Tegenaria domestica*). [2]
  • It can be found behind fireplaces, under sofas, and in baths. [2]
  • Some sources treat it as one species, while others treat it as three species: *E. atrica*, *E. duellica*, and *E. saeva*. [3]

Questions and answers

Are there giant house spiders in Canada?

The giant house spider is found in parts of Canada, particularly in British Columbia, where it was introduced from Europe. It thrives in homes and other buildings [1].

Is it safe to sleep in a room with a big spider?

Yes, it is generally safe. Giant house spiders are not aggressive and rarely bite. They prefer to flee rather than confront humans [2].

What to do if you see a giant spider?

If you see a giant house spider, you can leave it alone or gently relocate it outside using a cup and a piece of paper. They are harmless and help control insect pests [2].

Do UK giant house spiders bite?

Giant house spiders in the UK can bite, but they rarely do so. Their venom is not considered dangerous to humans, and bites are usually no worse than a bee sting [2].

Sources

  1. Pestsense — pestsense.cahnrs.wsu.edu (retrieved August 3, 2026)
  2. Giant house spider — wildlifetrusts.org (retrieved August 3, 2026)
  3. Giant House Spider: Facts, Threats & Conservation | WARN — worldanimalrescuenetwork.org (retrieved August 3, 2026)

Sources last checked August 3, 2026. · More in Nature