Local Chimney Cap Replacement in Jacksonville

Chimney cap, crown or chase cover

A chimney cap is the metal hood and screen fastened over the flue opening at the top of a masonry chimney. The hood also goes by chimney rain cap, and its mesh by chimney screen or chimney spark arrestor. If your chimney is a framed box with a metal pipe out of the top, the flat lid on that box is a chimney chase cover, a different part with a different fix. Both get called a chimney cover, so we confirm which one you have before anything is measured.

What a cap has to handle

A cap keeps rain out of the flue, keeps birds and animals from moving in and holds back embers from a wood fire, all without choking the draft. NFPA 211 gives caps and spark arresters a section of their own, and the Brick Industry Association's chimney design note adds two points: ask the cap maker how a cap affects the flow of gases up the flue, and use a corrosion-resistant metal.

Chimney cap installation starts with a tape

Single-flue caps fit the clay flue tile that stands up through the crown. We measure the tile's inside for a slip-in cap, its outside for a cap that clamps around it, and how far it rises above the crown. BIA guidance calls for the tile to stand at least 2 inches above the crown, and a tile trimmed flush leaves a band-mount cap nothing to hold.

A chimney with two or more flues can take a cap on each tile or one multi-flue chimney cap, an outside-mount cover that spans the crown and needs a sound crown to fasten into.

Spark arrestor installation and the code

Spark arrestor installation on a masonry chimney follows Florida Building Code, Residential section R1003.9.2. The net free area has to reach four times that of the flue outlet. The screen must resist heat and corrosion at least as well as 19-gage galvanized or 24-gage stainless steel. Openings may not pass a sphere larger than 1/2 inch or block one smaller than 3/8 inch, and the screen has to come off so the flue can be cleaned.

Chimney cap repair or a new chimney cap

Slip-in and band-mount caps hold with set screws against the tile or a clamp band drawn around it, and outside-mount covers are anchored into the crown with fasteners in a compatible metal. Chimney cap repair can be as small as reseating a cap whose screws backed out. A bent hood, a split band or a screen pulled from its hood calls for a new chimney cap before the next front comes through.

A capped chimney that still wets the damper sends us to the crown and the joints around the tile next, since a cap does little against rain driven sideways or water soaking through the brick. Our guide on water in fireplace after rain walks through the other paths.

Stainless steel, copper or galvanized

A stainless steel chimney cap is the everyday choice, and the grade on the maker's spec sheet goes on the estimate. Some makers sell a Type 316 line, labeled marine grade, for houses close to salt water. A copper chimney cap weathers to a brown or green patina and needs copper or stainless fasteners, since copper touching galvanized steel attacks the zinc.

Animals, other appliances and factory-built tops

A cap keeps animals out and does nothing to get them out, so anything living in the flue comes out first through chimney animal removal. Chimney swifts are protected under the federal Migratory Bird Treaty Act, and a flue with an active swift nest waits until the birds have gone. A flue that vents a furnace or water heater follows that appliance's venting instructions, and a factory-built metal chimney takes the cap listed for its system. Where the throat damper no longer seals, a top sealing damper with a lid and screen can stand in for the rain cap.

Call (904) 920-5495 and ask for a free inspection of the flue top.