Any gaps in siding, soffits, windows and penetrations is an invitation for insects and wasp. Wasp Nest can grow quite large inside these areas and Yellow Jackets are very aggressive and even more so in the Fall. If you have these nest inside the walls, the best course of action is to hire a qualified Pest Control Company. Its not likely you will be able to deal with this yourself and doing so may create a bigger problem. Wasp and Yellow Jackets can be deadly too. There have been several fatalities in our area from Yellow Jackets. By: South Alabama Home Inspections 2514909892