Absolute Chimney and Fireplace Restoration

Even though a chimney cap is a minor and relatively inexpensive installation, many homeowners question whether it is necessary. A chimney cap helps prevent animals from entering your home, keeps moisture out, and protects the roof from burning embers that could start a house fire. It’s a smart upgrade for most homes.

A common rule is: the chimney should extend at least 3 feet above the roof surface it penetrates and 2 feet higher than any roofline or other obstacle within a horizontal distance of 10 feet. Taller chimneys can make more draft, but chimneys exposed to outside cold can draft less.

Most masonry chimneys are brick or block on the exterior and have a liner on the inside. The liner’s purpose is to keep the heat of flue gases contained so the chimney doesn’t overheat nearby combustibles (framing, walls, etc.), which can reduce fire risk.

A chimney liner (also called a flue lining) is a clay, ceramic, or metal conduit installed inside a chimney. It helps contain combustion products, direct them to the outside, and protect chimney walls from heat and corrosion.

Building regulations don’t always require a liner if a chimney can be proven sound (via testing), is sized correctly for the appliance, can be connected properly, draws within manufacturer specs, and is sweepable—while meeting all applicable requirements. In practice, this can be complex, and many installers won’t proceed without a liner due to safety/performance concerns.

A flue is a duct, pipe, or opening in a chimney that conveys exhaust gases from a fireplace, furnace, water heater, boiler, or similar appliance to the outdoors. Historically, the term “flue” was sometimes used to refer to the chimney itself.