Chimney repair with a free inspection in Florida Center North

The crown is the roof of a masonry chimney

The top of a masonry chimney is its roof. Homeowners call it the crown, and the Florida Building Code calls it the chimney cap. The code wants it made of concrete, metal or stone, pitched so water runs off, with a drip edge and a caulked bond break at every flue liner.

Every part of that list does a job. The slope sends rain off the top instead of letting it sit. The drip edge lets water fall clear of the brick faces below. The bond break keeps the liner and the cap from being locked into one rigid piece.

Wear tends to show at the surface and the edges first, as cracks, crumbling corners or low spots where water now stands. Our chimney crown repair service handles the fix, and the estimate for homes in Florida Center North says which part of the crown has failed and whether it can be repaired or has to be replaced.

What a rain cap does and what it cannot do

A rain cap sits over the flue outlet and keeps rain and debris from dropping straight down the lining. That spares the damper, the smoke chamber and the firebox from water that would otherwise run down inside.

Three details matter when one is chosen. On a masonry chimney, the Florida Building Code sets the open area under a rain cap at no less than four times the area of the flue outlet it serves. BIA guidance says to get the maker's information on how a manufactured rain cap affects gas flow, and it says a metal cap should be corrosion resistant. A cap that restricts the outlet, or one that rusts, trades one problem for another.

What a rain cap cannot do is protect the crown around it. Rain hitting a cracked crown still soaks into the masonry, cap or no cap. Our chimney cap replacement service fits the cap itself, and when the crown underneath is failing, your Florida Center North estimate says so on a separate line.

Base flashing and counterflashing work as a pair

Where a chimney passes through the roof, two layers of metal keep water out. Base flashing goes in first. It turns up the face of the chimney and runs out along the roof, and the roofing laps over it, so water on the roof flows across the metal rather than into the joint.

Counterflashing comes second. It is set into the chimney masonry and laps down over the top edge of the base flashing, covering the gap where that layer meets the brick. BIA guidance has the counterflashing lap the base flashing by at least three inches, while the Florida Building Code requires counterflashing on a shingle roof to be corrosion-resistant metal of a set minimum thickness.

When either layer is missing, bent, loose or rusted, water can find its way behind the other. The fix belongs to our chimney flashing repair service, and the estimate says which layer failed and which one stays.

The air space between chimney and framing

A masonry chimney is not supposed to touch the wood around it. The Florida Building Code requires an air space between the chimney and combustible material, larger for a chimney inside the house or within an exterior wall than for one entirely outside it. That space may not be filled with anything except the fireblocking the code calls for.

A renovation can close that gap without anyone noticing. Trim and sheathing edges may meet the chimney only where they sit far enough from the flue lining, which the code also spells out.

Our crew looks at the chimney where it passes floors, ceilings and the attic whenever it is part of a repair. Anything crowding it, like the examples below, goes on the estimate with what it takes to restore the space.

• Drywall butted tight against the brick
• Paneling or shelving fixed straight to the chimney
• New flooring or trim laid hard against the chimney face