When we bought our house in 2008, we knew the chimney leaked – but not how bad. It turned out the chase cover (the metal sheet covering the top of the chimney) had rusted through and no one knew how long it had been like that.
The fireplace was hardly used so every rainfall it would get soaked, then dry out, soak then dry out. When we moved in, the fireplace was completely rusted out along with everything behind it.
Instead of having it fully fixed, we had a gas insert installed, but in retrospect we wish we would’ve done it right from the start. A roofing company I’ve worked with in the past recommended a fireplace vendor and we’ve determined the best course of action is to replace the gas unit and rebuild the original fireplace.
Even the gas unit is rusted out because it wasn’t able to be properly installed due to the prior rust.
Live and learn, and then do it right!