Cluster flies are often mistaken to be houseflies; however, they are unique in their physical appearance, breeding practice, and life duration.
Cluster Flies are slightly larger than houseflies, ranging from 1/4" to 3/8". They are dark grey or black in colour, with yellow hairs under the base of the wings where they attach. Cluster Flies can be distinguished from other flies by the way its wings are held over its back while resting--the wings are held flat, with the tips overlapping. Cluster flies are nuisance pests. The adults feed mainly on flowers, and the larvae feed on earthworms. They do not carry with them the health problems associated with filth-breeding houseflies and flesh flies (ie. eggs are not laid in fecal matter). Once inside my house, Yes, but it can be difficult once they've gained access to the inside. While cluster flies do not breed inside homes, they hibernate in wall voids and other difficult to reach places. Cluster flies lay their eggs outside in soil, as the emerging larvae requires earthworms to survive. Therefore, the more earthworms there are outside the home, the more likely a homeowner will experience cluster flies inside their home over the fall and winter. This is probably a survival strategy in cold wallvoids and atticks. I older homes it is not unusual to find layers of dead flies in an attick. Typically, cluster flies become a nuisance inside home and buildings during late summer and early fall, as the weather begins to cool off. Adult flies search for a protected site in which to rest over the winter. They enter home through vents and cracks in siding and shakes in large quantities. It is often true that they will congregate on the sunny side of a building (the south and west sides) before entering. Once they are inside their is no cost effective way to get rid of them except by the use of a vacuum cleaner when you find a cluster. Pesticides will only get rid of the outside layer and the rest will survive. The best time to prevent entry into your home is in early fall when they emerge for the last time of the season. This is when the outside of the building should be treated with a residual pesticide.

• Drain flies are one of the small flies 2-3mm long.
• Their body is covered with dense hair, which make them look like a moth.
• Their wings are longer than the body, when they rest the wings are folded over their body like a roof.

• They are not a major problem in most cases, except in homes with poor sanitary conditions
• They may also be an indication of broken down plumbing drain or sewer pipes.
• Drain flies are not strong fliers and are more likely found walking around sink and floor drains.
• They are often found in homes that are near a sewage treatment plant.
• Control can be difficult when they come in from the outside.

• Their life cycle is somewhat longer and therefore are not seen in great numbers.

• Drain fly larvae live submerged in the film of decomposing organic matter.
• In homes they may be found in plumbing water traps and garburaters.
• Often found outdoors near sewage treatment facilities.

• Even though these insect are living in the most unsanitary condition they are not known to spread diseases.
• When they are breeding indoors all drains, particular those in the floor must be cleaned using a steel brush or such like instrument.
• If they come in from the outside use fine mesh screens on doors and windows. Premier Environmental fly and insect screens for windows and doors are available at http://www.premier-env.co.uk.
• The use of pesticides has minimal effect.