Water Is Getting Into the Fireplace
If you find water pooling on the smoke shelf or see rust on your damper, there is a good chance rain is coming straight down the flue. A properly fitted cap covers the flue opening entirely and sheds water away from the liner and smoke chamber. Without one, every rain event soaks into your masonry from above.
The distinction worth making: if the water is entering at the roofline rather than down the flue itself, a cap will not fix it. That is a flashing repair issue, not a cap issue. We see homeowners install new caps when the actual source of moisture is failed step flashing around the chimney base. The inspection tells you which problem you actually have.
Learn more about how long chimney leak repair in Dallas takes once the correct problem is identified.
