The Brown Marmorated Stink Bug (BMSB), like many other bugs, tries to enter warm buildings when cold weather approaches. When it comes to avoiding an all-season battle with these bugs, the best defense is a good offense.
Since the Stink Bug can flatten its body and squeeze through small gaps, it is recommended that you spend time going around your home and repair screens, fill cracks around windows, door jams, baseboards, electrical/gas/plumbing entryways into the building, etc. Anywhere you find small cracks or holes, you should caulk or fill to prevent these bugs from entering. This will help reduce the number of entry points available to these pests.
So what do you do about the one’s on the side of the building, sunning themselves? Or those that did get into the building? Professional help includes applying a crack and crevice treatment outside your home that leaves a residual material to kill the bugs when they land on the treated areas. Inside your home, prepare a tray with equal parts of water and dish soap. Leave the tray in a place where small children or pets cannot get to it. The bugs will find it, fall in and drown.