I've got a basement fireplace that's been letting in water during heavy rains—it's pretty saturated around the bottom bricks, and moisture seeps out about a foot around the base. The chimney stack runs up through the garage, making it tough to dig down and fix things. An earlier contractor put in some interior drain tile, but that didn't work, and they tried again at no cost, going deeper, but the leak continued. Now, this new contractor recommends installing their aqua stop gutter system, which involves digging around the fireplace inside, creating a gutter in the floor to catch water, and adding a vapor barrier up the wall. They would then frame and drywall over it. We don't use this fireplace, and it's in a carpeted area without an ash cleanout. My main worry is whether the bricks will stay wet behind the wall and affect the structural integrity of the fireplace and chimney above. However, it looks like the upstairs chimney is built on a foundation that surrounds the downstairs part, so maybe it's not an issue. Here are some pictures for reference: https://imgur.com/a/vkwKjqn
1 Answer
I think you're looking at a reactive fix here. Before doing anything else, I’d check if there’s proper flashing on the chimney and see if it has a rain cap. It might need some tuckpointing or sealing of the masonry. Those issues can lead to leaks too, so don’t overlook them!
I actually tried covering my chimney with a tarp to stop any leaks, but it didn’t help. I found other issues and am getting new flashing, a cap, and tuck pointing done next week. Plus, I'm putting in a French drain since my driveway slopes toward the garage. It's a 1954 house, and this leak just started recently, so I'm trying to cover all bases!