Finding information about chimneys can be easy. However, some of the terminology used when describing a chimney may be a bit confusing. It is important to know what the words mean in order to understand exactly what you are reading. Otherwise, you would just be reading and not really absorbing. Here are some of the most commonly used words that you will find when doing research on chimneys.
Draft is what makes a chimney work. Draft is the process by which the warm air rising up and out of the chimney meets the cooler air at the top and allows fresh replacement air to be drawn back in. Excellent draft within a chimney allows for the smoke and harmful gases that come from the fire in the fireplace to be exhausted from the home rather than spill into it.
A Chimney Flue is the path on the inside of the chimney that the smoke and harmful gases follow on their way out of the house. The chimney flue should have some kind of chimney liner in it so that the smoke and gases are not absorbed into the masonry of the chimney
A Chimney Liner is a lining for the flue that helps protect the masonry of the chimney. Liners are generally made out of one of three materials; terracotta or clay, cement or metal (stainless steel or aluminum). A chimney liner serves several purposes such as protecting the masonry, improving draft and reducing creosote buildup.
Creosote is a substance that results from the burning of wood in a fireplace. It is usually black or dark brown in appearance and can be sticky or hard and crumbly to the touch. It is a highly flammable substance and can cause chimney fires if allowed to build up too much. Creosote is formed when the smoke rises in a chimney and cools and condenses. This substance can also hinder the draft within the chimney.
The Fireplace or Firebox is where the fire is actually built. From inside a house, the firebox can be seen, all of the parts within it are concealed.
The Smoke Shelf is a small, flat area above the chimney damper but below the flue. The smoke shelf is responsible for catching small amounts of rainwater and debris that may make it way into the chimney and down the flue. Large deposits of creosote can form here and it must be cleaned often. Also, if an animal makes its way into the chimney, this is likely where it will build a nest.
A Smoke Chamber is located just above the smoke shelf and below the chimney flue. This is the area where smoke gathers before its path up the chimney. Due to the lingering smoke, large deposits of creosote may accumulate in this area.
The Chimney Crown is the cement cap at the very top of the chimney. The surface of the crown should always be sloped away from the flue so that rainwater flows off of the chimney and not into it. The crown should be inspected regularly for cracks for water leaking into the cracks and cause rapid deterioration of the chimney.
Chimney Cap works for the chimney liner like the crown does for the chimney. It protects the chimney liner from rainwater, debris and animals that would otherwise get into the liner and hinder the proper functioning of the chimney. Also, there are draft enhancing chimney caps that use turbines to increase the draft.
The Thimble or Breech is the access to the chimney through which a freestanding wood stove or furnace connects to a chimney.
A Cleanout Door is usually located on the outside of the chimney a few feet above the ground. Through this door, some of the creosote and soot can be cleaned out of a chimney. It is imperative that this door be tightly sealed and closed when the fireplace is in use in order to prevent cold air from getting into the chimney and hindering the draft.
A Chimney Pot is a clay or ceramic topper for a chimney. The chimney pot can be very ornate or simplistic in design. By increasing the height of a chimney with a chimney pot, the draft within improves greatly.
Chimney Flashing is the metal flashing that wraps around the outside of a chimney where is meets any part of the roof. The chimney flashing is responsible for keeping water out of the roof. It is heavily sealed all the way around the chimney and tucked up underneath the shingles.
A Chimney Sweep is considered to be one of the old professions in the world, for, as long as there have been chimneys, there has been a need to keep them clean. A professional chimney sweep should be hired at least once a year in order to ensure that your chimney is in tip-top shape for the burning season.
These terms are important to know when trying to learn anything about chimneys. Whether you are trying to find a chimney professional for inspection, learning how to do some chimney maintenance on your own, or building a chimney on your house, it will be helpful to know these terms so you are not left in the dark when they are being used to describe something to you.