The Problem
The homeowner called after noticing water stains on the ceiling around the fireplace during heavy rains. Our inspection revealed the chimney crown had fractured into three large pieces, with gaps wide enough to insert a finger. The original crown was a flat mortar wash - common in 1970s construction but inadequate for long-term water protection.
Beyond the crown, the chimney’s mortar joints were deteriorated on all four faces. The step flashing where the chimney meets the roof had pulled away from the brick, creating a second water entry point. Water was entering from both the top and the side - explaining why the leak had gotten dramatically worse over the past two winters.
Our Solution
We demolished the existing crown completely, removing all fractured material down to the top course of brick. The new crown was formed with a proper 2-inch overhang and drip edge on all four sides, sloped away from the flue at a minimum 1/4 inch per foot. We used a fiber-reinforced concrete mix rated for exterior exposure and freeze-thaw resistance.
All four chimney faces were repointed with Type N mortar after removing deteriorated joints to 3/4 inch depth. The old step flashing was removed and replaced with new lead-coated copper step flashing set into fresh mortar joints - a detail that costs more upfront but eliminates the failure point that caused this leak.
A new stainless steel chimney cap was installed over the flue to prevent rain, snow, and animal entry.
The Result
The rebuilt crown, new flashing, and repointed joints eliminated all water entry points. The homeowner reported zero leaking through the following winter and spring, including during a heavy March rainstorm that previously would have produced visible ceiling stains within hours.
