The two most common species found in this country are the Oriental cockroach and the German cockroach.

The Oriental cockroach ranges from 20 – 30 mm in length and is almost black in colour. The German cockroach is much smaller at 10 – 15 mm in length and is brown in colour.

Where they are found

The German cockroach will inhabit warm, damp places such as laundries, kitchens and bathrooms.

The Oriental cockroach prefers cooler temperatures and is often found in cellars, basements and service ducting. They will also be found in the cooler areas in kitchens and bathrooms.

Both Oriental and German cockroaches are primarily nocturnal and will only be seen during the daytime when their harborages are full. Harbourages will be located in inaccessible areas beneath kitchen units, baths and showers. Cockroaches need access to a source of water, so will often be found in the vicinity of sinks and drains.

Spread of disease

Cockroaches can spread disease, as they typically inhabit unclean areas and may then walk over food preparation surfaces, thereby contaminating food intended for human consumption. However there are no specific disease linked to cockroaches and evidence of direct disease transmission is scarce.

Control methods

Cockroaches can be eradicated using broadband insecticides, which are only available for professional use. It is very important that you prepare the property appropriately before spraying; empty all kitchen cupboards and pull all furniture away from the walls. Furthermore it is important that you keep all foodstuffs in sealed plastic containers and empty dustbins regularly.

Signs of a cockroach problem are:

Seeing live insects – cockroaches are nocturnal and hide during the day. You will most likely see them when turning on the light in the kitchen at night.

  • Egg cases and cast skins – cockroaches shed their skin 5-8 times as they mature
  • Droppings – cockroaches leave a dust of black droppings less than 1mm wide and of varying lengths
  • Odour – established cockroach infestations produce an unpleasant, musty smell
  • Damage – cockroaches will attack organic goods including leather and books