Good points about the flashing and mortar joints. I had a similar issue when I bought my first fixer-upper a few years back. At first, I thought it was just the flashing too, since it was visibly rusty and loose in spots. Replaced it completely, thinking I'd solved the problem... but nope, still had leaks during heavy rain.
Turned out, the chimney crown itself had hairline cracks that were letting water seep through slowly. It wasn't obvious at first glance because the cracks were tiny—barely noticeable unless you got up close and personal. Ended up sealing the crown properly with a waterproof coating, and that finally did the trick. Been dry ever since (knock on wood).
So yeah, definitely check the flashing thoroughly, but don't overlook the crown either—even tiny cracks can cause headaches down the line. Speaking of which, has anyone here tried those flexible waterproof coatings for chimney crowns? I've heard mixed reviews—some swear by them, others say they're just another temporary fix. Curious if they're worth the effort or if it's better to just bite the bullet and redo the crown entirely...
"Speaking of which, has anyone here tried those flexible waterproof coatings for chimney crowns?"
I gave one of those flexible coatings a shot about three years ago. Initially, it seemed great—easy to apply and stopped the leaks immediately. But after about two winters, tiny cracks started showing again. Ended up redoing the crown completely last summer, and honestly, wish I'd done that from the start. Might depend on your climate though... colder winters here seem pretty tough on those coatings.
Ended up redoing the crown completely last summer, and honestly, wish I'd done that from the start. Might depend on your climate though...
I tried something similar on our old Victorian a few years back, and here's what worked well for me. First off, I thoroughly cleaned the crown surface—got rid of dirt, moss, and loose material. Then applied a masonry bonding primer to help the coating stick better. After that dried completely, I put two generous coats of the flexible waterproofing stuff, waiting at least a day between each coat. It's been about four winters now and still holding strong, even with our harsh freeze-thaw cycles. Maybe prep work makes all the difference?
After that dried completely, I put two generous coats of the flexible waterproofing stuff, waiting at least a day between each coat.
Interesting to hear your prep approach made it through four winters already—that's pretty impressive. I've been debating whether to tackle my chimney crown next or just redo the flashing first, since that's where I think the leak's coming from. Did you notice any leaking around the flashing area too, or was your issue strictly crown-related? Trying to prioritize here since budget's a bit tight...
I had a similar issue a few years back, and honestly, I chased my tail for a while thinking it was the crown when it turned out to be the flashing all along. Flashing leaks can be sneaky—they don't always drip straight down where you'd expect. Mine was actually running along the underside of the roof decking before finally dripping into the attic. Took me forever to figure that one out...
If you're tight on budget (been there, done that), I'd probably start with the flashing first since it's usually cheaper and easier to tackle yourself. Plus, if you do end up needing to redo the crown later, at least you'll have eliminated one potential source of leaks already.
One thing I'd suggest is getting up there with a hose on a dry day and spraying around the flashing area first—just isolate that spot and see if you get any water coming through. If nothing shows up, move up to the crown next. It might save you some guesswork and unnecessary spending.
Also, just a heads-up from experience: if you're going to redo flashing yourself, make sure you use good quality roofing sealant or even better—step flashing with proper counter-flashing. I tried cutting corners once with cheap caulk and ended up redoing it again two seasons later...lesson learned.
Good luck with it—chimney leaks are definitely one of those DIY projects that can test your patience!
