The main flies to bother man are houseflies, blue bottles and cluster flies. Houseflies are easily dealt with by proofing or simple fly spray. It is sometimes possible to find the source of blue bottle infestations, usually in the form of rotting animal waste somewhere. Cluster flies are the biggest problem as they invade spaces (lofts mainly) in the late autumn in huge numbers. This usually requires fumigation, once in late Autumn and again a few weeks later if the weather remains fairly mild and the flies remain active for a longer period.

During October, cluster flies will try to get in through gaps in poorly fitted windows on the sunny side of a house, often in large numbers. In this case a special residual acting insecticide may be sprayed all around the window frame to deal with these circumstances.