Chimney Flashing Repair in Pasadena: Written Report, Licensed Technicians

The brick chimneys in Bungalow Heaven historic district were built in the 1910s and 1920s, and the flashing that seals them to the roof was never designed for the freeze-thaw and ember exposure we see now. When water sneaks past cracked counter flashing, it soaks into century-old mortar, and that hidden moisture is what turns a small leak into a structural problem. After the recent Eaton Fire pushed embers across the Altadena foothills, we found flashing joints warped by heat on homes that never caught fire directly. Warped metal lifts away from the brick, and the gap it leaves lets rain follow the flue straight into your ceiling.

Here's what that costs you. A chimney that takes on water can crack its liner from repeated wetting and drying, and a cracked liner leaks carbon monoxide back into the house instead of venting it up. Near the Rose Bowl area, where many homes sit under mature oaks, we also see debris pile against the flashing and trap standing water through the whole rainy stretch. Roughly one in three leak calls we run traces back to flashing rather than the crown or the masonry itself. If your ceiling stain sits near the chimney chase, the flashing is the first thing worth checking, not the last.

A flashing repair done to code has two separate layers, and skipping one is why so many patch jobs fail by the next rain. Step flashing tucks under each course of shingles and laps up the chimney brick. Counter flashing then sets into a cut mortar joint and laps over the step flashing, so water sheds down and out instead of pooling behind metal. CSIA-trained inspectors follow NFPA 211 Level 2 protocol after any event that could damage the system, which includes fire exposure and earthquake movement, and that camera scan tells us whether the leak is truly the flashing or a cracked crown feeding water down behind it.

For the wide chimneys common on Pasadena's older homes, we install a cricket, a small peaked diverter on the uphill side that splits rain around the masonry rather than letting it dam against the base. We favor lead flashing over aluminum here because lead molds tightly into irregular pre-war mortar joints and shrugs off the salt-tinged marine air that corrodes thinner metal. Timing matters too. Getting the work done before the winter storm cycle means the sealant cures dry. Our repairs follow NRCA roofing and flashing best practices, and when the surrounding brick needs attention we handle that in the same visit.