Maintenance and cleaning of your fireplace

A masonry fireplace is custom-built of bricks and mortar. The firebox is constructed of firebricks, and the flue consists of brick or a clay or terra cotta liner. Firebricks and the mortar that surrounds them are intended to withstand extreme temperatures.

Prefabricated metal fireplaces often need more frequent cleaning. They burn cooler, allowing a higher degree of condensation of combustion deposits on the interior surface of the fireplace flue. A prefabricated metal fireplace is installed and assembled on-site. The metal box contains firebrick panels, called refractory brick panels, that line the sides, back, and bottom of the firebox. The flue for a prefabricated fireplace consists of a metal pipe that is concealed by a chimney constructed of plywood or another siding material.

• Dealing with the Damper - The damper is a steel or cast-iron door that opens or closes the throat of the firebox into the flue. It regulates draft and prevents the loss of heat up the chimney.

• Cleaning a Soot-covered Fireplace Face
Oils and soot make an otherwise handsome brick fireplace face look tired and tattered. To reduce the effect of oils and soot, regularly vacuum a brick face and hearth and periodically wipe them down with a damp sponge.

• Failing to maintain your fireplace properly can lead to a chimney fire - Chimney fires occur when combustible deposits on the inner walls of the chimney ignite. These explosive deposits, called creosote, are a natural byproduct of combustion. A fire hazard exists if 1/8 to 1/4 inch of creosote (or more) coats the inner walls of the chimney, creating a time bomb waiting to go off. A chimney fire can literally level your house.

• Cleaning Glass Doors and Screens
A fireplace exhausts smoke in a sort of siphon action. Once heat begins to rise through the stack, the siphon continues to draw air from within the house. In this way, the fireplace actually removes warm air from your home. To offset the problem, you can install glass doors and add outside air ducts.

• Fireplace Cracks - No matter what type of material is used to construct the firebox (the place where you burn the wood) they are designed to withstand extreme temperatures. However, over time, the brick, mortar, or panels can crack and crumble, creating a serious fire hazard. In a masonry fireplace, firebrick is used to construct the firebox (the place where you burn the wood). Refractory brick panels line the firebox of a prefabricated metal fireplace. In both cases, the bricks and fireclay mortar are designed to withstand extreme temperatures. However, over time, the brick, mortar, or panels can crack and crumble, creating a serious fire hazard. If the brick is crumbling, it should be replaced with a new firebrick embedded in refractory mortar.

Crumbling mortar joints in a firebox should be chiseled out and replaced with new refractory mortar. (Refractory mortar is specially designed to withstand high temperatures.) This process, known as tuckpointing, is the same as replacing or repairing mortar joints in any brick structure. The only difference is that in a firebox, the mortar must withstand extreme temperatures.

If the integrity of the majority of the firebrick and mortar in the firebox is in question, a qualified chimney sweep or masonry contractor should inspect it. If replacement is in order, this is a job that is best left to a pro.

Repairing minor cracks and mortar joints in prefabricated metal fireplaces is essentially the same as with a brick firebox with one exception. If a panel develops extensive cracks or is beginning to crumble, it should be replaced with a new panel.

Chimney sweeps are equipped to do more elaborate inspections with a video camera and monitor referred to as a "chimscan." The chimscan is more costly than a visual inspection, but will reveal more and better information about the condition of a chimney. This is especially important when the integrity of the flue is in question due to age or damage from an earthquake or chimney fire.

• Caring for the Outside of Your Chimney
A chimney can be either an exposed pipe, a framed enclosure that is covered with siding that houses the flue pipe, or a masonry chimney. In all cases, it travels from the inside of the home to the outside either through a roof or out a wall. The point where the chimney exits the structure is a primary source of leaks.