Fireplace Chimney Construction

Masonry Chimney Construction

Construction of a masonry fireplace chimney should always be done by a certified professional mason. If the chimney is not constructed properly, there is a risk of uncontrolled smoke release from the home which could burn the house down. After the masonry fireplace has been constructed, the chimney construction begins with the installation of a damper. The damper is the "door" at the top of the fireplace which can open and close. It must stay open to let the smoke from the fire up the chimney. It can be closed during cold outside weather not during a fire in the fireplace to prevent loss of heat from the home. After the damper is installed, the "throat" needs to be constructed. The smoke that travels through a masonry chimney goes through clay flu. The clay flu normally does not fit directly on top of the damper, therefor you need to construct the throat in order to connect the clay flu on top of the damper. The throat for a masonry fireplace chimney is usually constructed using concrete block. After the throat has been constructed, the clay flu can be "stacked" on top of one another using fire safe cement to close the joints between each flu pipe. The flu runs up the length of the chimney and sticks out of the top of the chimney. With exception to elaborate masonry chimney top designs, the flu pipe is usually the highest point at the top of the chimney. With a masonry fireplace chimney, the damper, throat, and flu are surround by concrete block or brick to construct the chimney to the top. In most cases, the code for chimney height is 3' above any point of the house within 10' of the chimney.

Vented Fireplace Chimney Construction

Vented fireplace chimney construction differs from masonry fireplace chimney construction in that masonry materials such as concrete block, mortar, and clay flu are not typically used. Vented fireplace chimneys most commonly consist of metal pipe which serves as the exit for the smoke from the home. The perimeter of the chimney is usually constructed using common wood framing materials. The exterior of the vented fireplace chimney can then be faced with brick, stone, stucco, wood siding, or vinyl siding. Vent free fireplaces do not have a chimney.

fireplace chimney