They find their way in through cracks or gaps in exterior walls, through doors, windows, chimney tops, and screens in need of mending. Having found their way in, they nestle in attics, crawlspaces, vents, and any dark place. They can sometimes even be found in piles of clothing and in luggage. Generally, they hibernate throughout the winter, and if you're lucky, you won't even know they're there. When warm weather returns, they become active once more and begin to migrate outdoors. However, during sunny winter days or when the heater warms up their quarters, the warmth can rouse them into activity. Attracted to light, they might fly towards light fixtures or just move about the house
The best way to avoid this scenario is prevention. As early as late summer or as late as fall, walk around the perimeter of your house, looking for any crevices or openings in sidings, wood facia, and walls that may serve as entrances to stink bugs. Any hole that's larger than the diameter of a pencil should be sealed. Inspect door and window frames, ensuring that doors and windows fit tightly. Check if any of your screens - including attic and crawl space air vent screens - are broken, and repair those that need it. Inspect chimneys and drain pipes as well. Finally, trim any vegetation you have around your house, ensuring that no plants touch the walls of your house. It's best to leave a space ranging from 12 to 20 inches between plants and house.
At times, it may prove difficult to seal off the house completely. In this case, some homeowners opt to call pest professionals to pre-treat their house for them. To keep stink bugs at bay, professionals spray house exteriors with pesticides, especially around possible entry points, and apply insect granules for several weeks before the onset of cold weather. However, insecticides are usually not as effective or long-lasting as is a proper sealing of the house.
If you're looking for further information about how to get rid of stink bugs, and prevent them from infesting your home before its too late, be sure to check out Free your home from stink bugs in a easy way