One of the most common type of plumbing vent caps in Minnesota is a two-piece frost-resistant plumbing vent cap, which has a piece of lead that can be bent to fit over a plumbing vent, preventing water leakage. They're easy to install, there's no rubber flange at the bottom that will eventually split, and they're made right here in Minnesota. The only downside?
They're magically delicious.
Lead apparently has a sweet taste, and was used in Ancient Rome to sweeten wine. Squirrels like to gnaw on those sweet lead caps, and once a squirrel develops a taste for lead, they just can't seem to help themselves. They keep coming back. I suppose all that lead can't be good for squirrels, but the main focus is how this affects one's house. Once a plumbing vent cap is damaged, water can leak into the attic between the plumbing vent and the cap. The photos below show a few examples
The wrong way to repair the cap is to goop it up with tar. This is ineffective and temporary.
Another wrong way to deal with a damaged gap is to use caulk.
Another wrong way to deal with this is to install some kind of goofy cap.
The proper and simple way to deal with a damaged cap is to replace it. Most caps are loose enough to just slide right off without any tools. Check out the 15 second video below for a quick demonstration.
Replacement caps can be ordered online from F.J. Moore. Keeping trees and other vegetation trimmed away from your house will help prevent squirrels from getting onto the roof in the first place. If you want to go crazy with your repair so the cap never gets destroyed again, check out this permanent solution by Kuhl's Contracting.
Author: Reuben Saltzman, Structure Tech Home Inspections