Chimney Caps and Crowns in Downey, CA

Chimney Caps and Crowns for Downey Homeowners

Downey built out around work. The Spanish Colonial and Mediterranean houses near the old downtown date from the 1920s and 1930s, and then the city filled in hard through the 1950s and 1960s to house the Rockwell and North American Aviation workforce that built the Apollo command module here. That means the bulk of Downey chimneys are sixty to seventy years old, single-flue, terracotta-lined masonry serving a fireplace that was a design feature of the ranch house rather than a heating appliance. They have been used lightly and maintained rarely, which is the profile that produces the surprises. What we find most often in the postwar tracts is crown failure: a thin trowelled mortar wash across the top with no overhang, cracked through decades ago, quietly feeding water into the stack ever since. The rusted damper underneath is usually the first symptom the homeowner notices. In the older Spanish houses nearer downtown the issue is more often the firebox itself, where original firebrick has spalled and the joints have opened.

1950s-60s aerospace-era ranch tracts with failed mortar crowns, and 1920s Spanish houses with spalled original fireboxes.

An uncapped flue in Los Angeles County is an open pipe into your house, and it fills up. We pull nesting material out of chimneys here in every month of the year, because the birds and roof rats never get a winter off. The other thing an open flue takes is rain, straight down onto the damper and the smoke shelf, which is why so many dampers in this county are rusted solid. The crown matters just as much and gets thought about far less. A crown is meant to be a sloped, reinforced slab with an overhang and a drip edge that throws water clear of the brick. What most houses actually have is a flat trowelled smear of ordinary mortar, which cracks within a decade and then funnels water into the top of the stack. There is a fire dimension too: in the hillside and canyon parts of this county a spark arrestor screen is not optional, and a great many older chimneys either never had one or have one that has rusted through.