When I first started keeping Bp's (the aquarium days), my bp escaped by pushing out the screen cover. After about 1 month of looking everywhere in the house, plus trying every trick in the book my younger brother came running into my room and jumped on my sofa. I heard a very loud hiss and immediately I knew. To sum it up we found the snake but lost the sofa. He was so tightly curled around the inner springs that we had to completely dismantle the thing.