Chimney Cap Installation in Palos Hills, IL

Chimney cap installation in Palos Hills

Most caps here fail at the metal, not the masonry. Galvanized steel was the default on 1960s-70s brick chimneys. Freeze-thaw plus acidic flue condensate chews through the coating. Rust streaks run down the brick or the siding. Then the mesh lets go, and the flue sits open to rain, leaves and starlings.

Fit is decided at the tile, not the chimney. A single-flue cap clamps to the clay tile's outside dimensions, so we measure the tile, not the opening. Older corbelled chimneys often have chipped or shifted top tiles. A band clamp needs sound tile to bite. Two-flue stacks usually take one multi-flue cover anchored into the crown instead.

So the crown gets checked first. If it is cracked, thin or sloped off at the edges, anchors have nothing to hold. We say that before quoting a cap, not after.

Appliance type changes the screen. An orphaned furnace flue venting only a water heater runs cool and wet; fine mesh collects scale and lint and can choke draft. Factory-built chimneys are a separate job. A chase cover is not a cap, and Class A pipe takes the manufacturer's listed termination.

From the driveway, look for rust lines on the brick and twigs poking through mesh.