Chimney repair from the cap to the firebox in Richmond Heights

A chimney with more than one flue

Some chimneys carry two or more flues, one for the fireplace and others for a second fireplace or an appliance. Under the Florida Building Code, masonry wythes separate adjacent flue linings, built into the chimney walls, with an exception for two flues venting a single appliance.

Each flue brings its own top detail, and the masonry between flues cannot be seen from the roof, so every flue is checked from its own top. A cap over one flue with its neighbor left open still lets rain into the chimney.

Every flue gets its own findings on the estimate. That makes it clear which flue a repair belongs to, what that flue serves and whether a problem in one affects the use of the other.

• A liner standing above the crown
• Its own caulked bond break at the crown
• A cap that covers the flue it is meant to protect
• The top of the wythe beside it, as far as it can be seen

The cleanout door at the base of a flue

A small metal door at the bottom of a chimney, outside or in a utility space, is usually a cleanout. The Florida Building Code requires a cleanout opening close to the base of each masonry chimney flue, with a noncombustible cover, so ash and debris can be taken out. Fireplace flues that can be cleaned through the fireplace opening are the exception.

Cleanout doors rust, warp and lose their latches. One that is missing or hangs open gives animals and water an easy way in, and one rusted shut leaves debris sitting at the base out of sight.

Replacing the door is a small job, but the frame has to sit tight in the masonry so the new cover closes properly. The base of the flue is cleared first, then a noncombustible door and frame are fitted. Any of these signs puts the door on the estimate.

• A door that will not latch or close flush
• Rust holes or a warped frame
• Loose mortar around the frame
• Ash or debris spilling from the opening

Antennas, dishes and lights mounted on a chimney

A chimney looks like a handy post for a satellite dish, an old antenna, a flag bracket or a string of lights. The Florida Building Code lets a chimney carry nothing but its own weight unless it was designed and built for the added load. A chimney built to carry itself has no allowance for a mast pulling on it.

The damage tends to start at the anchors. Bolts and straps drilled into brick or mortar open holes for water, and a mast that moves works those holes larger. Straps wrapped around the stack can crack corners and hold water against the face.

The repair is taking the mount down, patching or replacing the drilled masonry and putting the equipment somewhere built to hold it. Our technicians remove what is on the chimney and the estimate prices the masonry repair. Mounting the dish somewhere else is a job for its installer.

Caring for a chimney after the repair

Fresh mortar, concrete and stucco need time to cure. The Florida Building Code sets waiting periods between stucco coats for that reason, and patching and sealing products usually carry their own. What care a repair needs depends on the material used.

Keep paint, sealers and coatings off new work until the product maker allows them. On newly laid brickwork a fairly even white film can appear as the masonry dries. Brick Industry Association guidance on efflorescence calls it new building bloom and says that in most cases it dissipates over time once the brickwork is allowed to dry. Bloom that keeps coming back is a different matter.

The first fire waits until the flue work is complete and cured. Before lighting it, ask whether the repaired flue is ready, because the answer depends on what was used and how long it needs. Keep ladders and foot traffic off new work at the top for a while as well.