The basic structure of an apartment building can be very inviting to many types of bugs. Once inside, it's easy for bugs to travel from one apartment to another when several units are connected by common walls and hallways. While there are many species of insects that make their homes indoors, some of the most common varieties of apartment-dwelling bugs are the centipede, earwig, silverfish and the cockroach.
The centipede is a yellowish-brown arthropod that measures about 1 inch long. It's distinguished by 30 pairs of long slender legs and a set of antennae that protrude out in front of its head. Centipedes prey on other insects and spiders, and while their habitat is normally outdoors, they also dwell in damp areas of apartments such as bathrooms or kitchens. If you can diminish the numbers of other insect varieties in your apartment, you will decrease the likelihood of seeing centipedes.
The earwig is a brown, beetle-like bug with enormous pinchers on its back end. These insects feed on both plant and insect matter, and use their pinchers for defensive purposes. Mature earwigs measure 1 inch from end to end and have small wings. Earwigs often live against outside apartment foundations, occasionally finding their way inside under doors or through open windows. The best way to keep earwigs to a minimum inside your apartment is to seal or use weather stripping on all doors and windows.
Almost alien in appearance, the silverfish is gray and coved in tiny scales. This insect measures three-fourths of an inch, not including the long antennae on its head or the three long tails that resemble legs at the end of its body. Silverfish have long life spans and may live anywhere from two to eight years. These bugs can be found in kitchens, bathrooms and basements, feeding on things like flour, oats or molds. The silverfish is fast-moving and prefers high humidity levels of between 80 and 90 percent and temperatures above 70 degrees. These insects enter apartments from cracks under doors or windows, so weather stripping and sealants can minimize their occurrence indoors.
The American cockroach can grow to approximately 1.5 inches long, and both young and grown roaches are brown. Females may be seen with egg sacs attached to their ends and they lay eggs monthly for almost a year. Roaches prefer high humidity and are found throughout sewer systems that enable them to enter apartments through drains in bathrooms and kitchens. Once indoors, they will move from apartment to apartment through walls, floors and ceiling spaces. A roach can squeeze through a crack as thin as a dime, making them a difficult bug to exterminate.