Have you ever had to sweep bat droppings out of your attic, or spent a summer struggling with wasps that you just can't seem to kill at the source? These are just a couple of problems from neglecting flashing repair. Bad or weak flashing seems a little problem when you first see it. The consequences of ignoring it have cost some homeowners their entire house.
Those seals and coverings around chimneys and vents, or guarding access to eaves, do more than keep rain from getting in. They keep vermin out as well. It would just amaze you how small a hole it takes for a bat to squeeze through — not to mention a yellow jacket. Rats can squeeze between your vent pipes and your roof, and just make themselves at home in your home.