The Oriental cockroach is larger than the German version of the species, a fully grown adult male will be up to 29mm in length, with the female slightly smaller, between 20 and 27mm. Whereas a German cockroach is brown in colour, the Oriental cockroach has a glossy black appearance.
They are harder to get rid of than other cockroaches as they can harbour outdoors as well as inside, coping with lower temperatures. They thrive in dark, moist places, so boiler rooms, sewage systems, bathrooms and organic matter are locations where infestations are most likely to start.
They can easily move around properties, meaning that a block of flats may be particularly susceptible to infestations that take over multiple homes. They will feed on a wide range of things, including waste food and faecal matter and can survive several months without food.
Professional and specific treatment is needed for this kind of pest, otherwise the likelihood of return is greatly increased and will ultimately lead to a higher cost and more difficult removal.