There are around a dozen different types of house spider in the United Kingdom. A spider is considered a house spider if its habitat is a house or outbuilding (garage, garden shed, etc). Most house spiders are nocturnal, spending their days motionless in their webs. They tend to eat mites and other small insects.
Tegenaria duellica is the most common form of house spider found in the United Kingdom. Tegenaria duellica has around a 10 millimetre body and head and 50 millimetre legs. They eat flies, mites and small insects and make thick webs in the corners of rooms, usually around 15 centimetres across. They become more noticeable in autumn, their mating season. The male spider has longer legs than the female, but the female has a broader abdomen.
Oonops domestica, or the pink prowler, are virtually exclusive to houses. According to the British Arachnological Society, they are tiny spiders around 2 millimetres. They are nocturnal creatures who spend their days hiding in their small web cells, usually behind furniture or curtains. Oonops domestica eats mites and other tiny insects.
Pholcus phalangioides, or the Daddy Long Legs, are only found inside buildings and are much more prevalent in the south of the United Kingdom. Daddy Long Legs feed on insects but will also eat other spiders, including their own kind. According to the British Arachnological Society, Daddy Long Legs stay motionless in their webs during the day and at night males go in search of females.
Scytodes Thoracica is commonly known as the spitting spider. It will approach its prey to within about 10 millimetres and then spit a fluid from its jaws which glues its prey to the ground. Scytodes thoracica is no larger than 6 millimetres and has cream-coloured body with black markings. Spitting spiders are more common in the south of the U.K. and are more likely to be seen at night.