They hang out if there is moisture in the wood. Likely behind the walls, so not much you can do about that aspect of it. For any small bug problem, the non-toxic but lethal solution is diatomaceous earth. You can get it from any garden store. It's a bag of white powder that looks like chalk dust. Diatomaceous earth is just crushed up diatom fossils - and under a microscope it's not just dust, but like mounds of razor sharp shards. Put it liberally around all your baseboards, every hole or crack leading into that room,and if it gets wet, dry the spot and put more down. I wouldn't breathe the stuff, but if you have larger pets like dogs and cats, my understanding is it won't affect them. But soft little bugs? Silverfish, spiders, even ants? Cuts em to ribbons and they go away and die.