LBI Pest Control offers carpenter bee exclusion as a service. What is that, you ask? Every spring carpenter bees show up, usually buzzing around the trim at the top of your roof line. What are they doing up there and why are they going under the trim on my roof? The trim is called the rake board and it is an unfinished piece of wood covered on the outside by a piece of aluminum. The back side of that wood is raw. Female carpenter bees will go under the vinyl siding and start to excavate their nest into that piece of raw wood. This is sometimes evident by the staining that you will see on your siding coming out from behind the rake board.