Carbon Monoxide - An odorless, colorless, tasteless poisonous gas that is a byproduct of incomplete combustion. Carbon monoxide can be fatal if not detected. Please see our Carbon Monoxide Page for more information.

Certified Chimney Sweep (CCS) - An individual The nationally recognized credential provided by the Chimney Safety Institute of America (CSIA) is the measure of a chimney sweep’s knowledge about the evaluation and maintenance of chimney and venting systems. A CCS credential holder is trained in the sweeping and inspection of different chimney systems, operation of the necessary equipment, health and safety considerations, codes, clearances, standards and practices of the chimney service trade.

Chase Cover - A metal cover that fits over your chimney chase (generally on chimneys with wood, metal, or vinyl siding) to prevent water from entering the chimney.

Chimney Chase - The area or structure around metal flue pipes. The chase is usually built with wood or steel studs with an exterior that can include brick/stone veneer or wood siding or stucco

Chimney - One or more passageways, vertical or nearly so for conveying flue gases from the appliance to the outside atmosphere.

Chimney (or Flue) Cap - A protective covering or housing for the top of a chimney. Often, chimney caps have a lid to protect from rain, snow and sleet and a screen mesh of some sort to keep animals out.

Chimney Cleaning (Sweeping) - The process of removing soot, creosote, and debris from a chimney. Soot and creosote are by-products of combustion and should be removed regularly from the chimney to help prevent a chimney fire. Chimney cleaning along with an inspection should be preformed as part of an maintence schedule to ensure your chimney operates as efficiently and safely as possible.

Chimney Connector - The pipe connecting a fuel-burning appliance to a chimney. Most commonly made from galanized steel, stove black pipe, or a listed double-wall pipe system.

Chimney Liner - The inner portion of the chimney that contains the products of combustion. It can be made of clay tiles or of metal. The flue chimney liner is one of the most important part of the chimney system. It must be able to contain the products of the combustion process. This means that any holes, cracks or deteriorations must be repaired or replaced to ensure the preformance and safety of the chimney system.

Corbel - Units of masonry projecting from or projecting upward and outward from the face of a wall or chimney in courses to form a support or ledge for a beam, rafter, or other member.

Cord (of wood) - The cord is a unit of measure of dry volume used to measure firewood and pulpwood in the United States and Canada. A standard cord is a neat stack of wood that has a volume of 128 cubic  feet. It measures 4 feet high, 4 feet wide and 8 feet long. This includes the air between the wood. The actual wood volume is usually around 90 cubic feet. See our article "What is a Cord of Wood?" for more information.

Corn Stove - A corn stove is designed for whole, shelled corn kernel combustion and is similar to a pellet stove. The chief difference between a pellet stove and a dedicated corn stove is the addition of a metal stirring rod within the burn pot, or an active ash removal system. These vary in design slightly, but usually consist of one long metal stalk with smaller rods welded at a perpendicular angle, in order to churn the burn pot as it spins. An active ash removal system consists of augers at the bottom of the burn pot that evacuate the ash and clinkers. During a normal burn cycle, the sugar content within corn (and other similar bio-fuels) will cause the ashes to stick together, forming a hard mass. The metal stirring rod breaks apart these masses, causing a much more consistent burn. 

Creosote - A type of carbon rich chemical released during the burning of wood and other fossil fuels when there is a lack of adequate airflow. As the smoke rises through the chimney it cools, causing water, carbon, and volatiles to condense on the interior surfaces of the flue. This appears on the flue as a hard, dark, and shiny coating.

Cricket - (also referred to as a Saddle) A ridge that extends from the back of the chimney to the slope of the roof, with the purpose of shedding water away from the connection between the chimney and the roof.

Crown - A chimney crown is the top surface of a chimney formed with concrete or mortar and poured on top of the chimney and extends out passed the stone or brick and typically has a drip edge built in to the underside to prevent water from entering the masonry below. Crowns generally have a slope away from the center of the flue stacks.

Crown Wash - The crown wash is much more popular because it is much more cost effective and is usually just cement sloped down from around the flue tiles feathered to the edge of the stone or brick.  Both share the common goal of keeping weather out from the very top of the chimney.

CSIA - The Chimney Safety Institute of America or CSIA is a non-profit, tax-exempt educational institution dedicated to chimney and venting system safety. Hiring a CSIA certified chimney sweep means your sweep has been trained and is up to date on industry standards and best practices. At minimum you r sweep should be supervised by a CSIA certified sweep.