Giant House Spider bites

The giant house spider as its name suggests is a great big spider often found in houses. Tegenaria gigantea, to give it its proper name, can have a leg span of up to a whopping 10cm (4 in). This size, combined with the spiders habit of dashing across a room and stopping in the middle, has made it an arachnophobes worst nightmare. Oh and it’s hairy!

Despite being called the house spider T. gigantea commonly resides outdoors. It lives in cracks and crevices where it spins a flat messy web leading to a funnel in the crack. Here the spider lurks until an unwary insect wanders into the web at which point the spider darts out and attacks.
The spiders are most often spotted indoors during the autumn, this is also when they have reached their maximum size. It is generally the male spider you will see and it is likely he is on the prowl for a lady spider with the aim of making some baby spiders. You can spot the male by the large pedipalps at the front – yes, you may be relieved to know they aren’t 2 huge fangs!

The spiders do set up home indoors too and can often be found in undisturbed corners or behind long forgotten boxes, i.e. as far away from humans as they can get.

The spiders habit of dashing across a room and pausing to scare the bejaysus out of everyone actually has a reason. They aren’t in fact doing it on purpose they are actually stopping for a rest. Holding the Guinness World Record for being the fastest spider on earth they rapidly tire themselves out!

Does it bite?

The giant house spider is big, hairy and very fast; but does it bite? Well yes, it can. Give its size it is one of the few British spiders with fangs big enough to reliably penetrate human skin. That said their venom is not particularly toxic to humans and from what I’ve seen they are very reluctant to bite even when mishandled.

The giant house spider is a close relative of the hobo spider (Tegenaria agrestis) which is found throughout western Europe and more recently in the USA. In Europe it is rare to see a hobo spider indoors as the indigenous house spiders keep them out. However, this is not the case in America where they are found in homes and considered both aggressive and capable of inflicting a serious bite. There seems to be some dispute at present as to whether the hobo spider’s bite can cause necrosis, i.e. a sort of brown recluse light.