DIY & Home Improvement

And when ever you open stuff up use copper mesh, it's a loose screen of copper which they are allergic to and will avoid. They also hate touching aluminum foil. You need to find their water source. That is likely the initial cause.
Good luck, it takes a lot of effort to seal up, especially a raised structure. I did my wife's summer spot a while ago, but they just got back in this summer. I didn't use copper mesh before. We just bought it.