Cluster Flies in the Loft

Over the last few weeks, the number of calls regarding Cluster flies in lofts have increased dramatically. So how do you know if you have Cluster Flies in the Loft and what should you do about them?

Firstly, What are Cluster Flies?

Cluster Flies are part of the blow fly family, but unlike blow flies, they do not pose a health risk as they do not feed on foodstuff, nor lay eggs in food matter. They are about 7mm in length and have distinct dark stripes behind the head. They are also relatively slow moving in comparison to house flies. They are parasitic on earthworms and lay eggs in earthworm holes, where the larvae hatch and feed on earthworms.

First signs of cluster flies will be lots of flies congregating in windows as they emerge from hibernation and head for the light. This can be in very considerable numbers and can be very distressing for the house owner and occupants. They enter the house via small holes and cracks in the ceiling, light fittings and even where beams join the ceilings. They are very difficult to eliminate as they tend to get into the smallest cracks and under insulation where normal chemicals fail to penetrate. They use the loft to hibernate over winter, hence having cluster flies in the loft is very common. They crawl in under the tiles and felt, then as they emerge from hibernation (which can be from March to August) they head for a light source, typically a light fitting or cracks in the ceiling. They can also become active when the central heating is switched on, making them believe its time to emerge.

ULV Treatment Machine for Cluster Flies in the Loft

ULV Treatment Machine

At Rapid Pest Control, we use highly specialised treatment methods which are very effective. Our treatments consist of ULV spray treatments in the loft area, plus the use of residual sprays and dusts at the entry and exit points. A ULV treatment is a method of delivering a lethal dose of insecticide, whilst protecting the environment.

ULV means Ultra Low Volume which basically only uses tiny amounts of insecticide but vaporises this chemical into microscopic droplets of 15 Microns, the optimum size to control insects and create a long lasting cloud and residual effect. Some of this chemical leaches into cracks and crevices where the Cluster Flies love to hide, thus killing them more effectively.

Other treatments include insecticidal smoke bombs, however these are not very effective or long lasting, and pose a fire hazard so Rapid Pest Control rarely use this type of treatment and would advise against this method of treatment.

So if you have flies appearing in your house, you will almost certainly have cluster flies in the loft, so we recommend you contact Rapid Pest Control now or call 01635 247192 to treat them.