Anatomy of a Fireplace
A while back, we went over the anatomy of a chimney. Now, it’s time to go over the anatomy of a fireplace. While you might think the structure of a fireplace is obvious, not all of its parts are visible at a glance. Knowing all of the pieces of your fireplace and their functions can help you to troubleshoot problems when they arise and communicate better with a certified professional chimney sweep when your fireplace is inspected.
There can be up to 12 parts of a fireplace:
1. Mantel: The mantel or mantelpiece is the shelf above the face of the fireplace. Some new fireplaces with a modern design may not have one. In most homes, it is the focal point of the fireplace. While its role now is entirely decorative, it used to prevent smoke from entering the home.
2. Lintel: This is the load barring piece above the opening of the fireplace. Windows, archways and doorways also have lintels.
3. Fireplace Face: The exterior masonry of the fireplace, from under the mantle to surrounding the opening of the hearth, is known as the fireplace face. It is made of brick, stone or concrete. These materials are used because they are strong enough to endure the heat from the firebox. While the fireplace face may seem like a decorative feature, its primary role is to protect the surrounding walls from the fire.
4. Throat: Behind the fireplace face, just above the firebox, is the throat. It is where the fireplace vents into the chimney. The damper to the fireplace is at the top of the throat. Recently, the requirements for the throat have been changed. The throat of a fireplace is now required to be 8 inches above the inner hearth instead of 6 inches. When smoke leaks into a home from the firebox, it is usually an indication that the throat was not constructed properly or needs to be repaired.
5. Firebox or Inner Hearth: When you watch flames dancing in the fireplace, you are looking at the inner hearth or firebox. It is the place where combustion occurs. The back of the firebox is lined with firebrick, which is specially formulated brick that is usually made from fire clay. Firebrick is used because it can withstand the potential corrosion from fuel and the extremely high temperatures of the fire. After years of use, firebrick can crack or become weakened. Due to this, it is recommended to have your firebox inspected about every five years.
6. Outer Hearth or Hearth Extension: The floor that extends in front of the firebox is called the outer heather. It protects the floors of your home from damage from the fire. It is made of heat resistant material like tile or brick.
7. Ash Dump Door: Under the middle of the firebox, there may be a door which can be opened to let ashes fall into the ash dump. This is the ash dump door. Not all homes have this feature. You may have to remove the ashes manually.
8. Ash Dump: The ash dump is the passageway the ash falls through.
9. Ash Pit: The ash pit is where ash collects after it has fallen down the ash dump. It should be emptied frequently to prevent the accumulation of flammable byproducts.
10. Footing: Under the ash pit is a horizontal surface, usually made of concrete, called the footing. Normally, the footing and ash pit are located in the basement.
11. Clean Out Door: For easy removal the ash pit has a door known as the clean out door. It may be located in the basement or outside.
12. Foundation: Supporting the chimney is a foundation that is usually made of heavy duty cinderblock or brick. It is made to withstand the heat of hot ashes and provides the structural support for the whole chimney.
When each part of your fireplace and chimney is functioning properly, you can enjoy the comfort of your hearth without anxiety. If you believe that any part of your fireplace is not functioning properly or needs to be cleaned, contact one of our chimney experts. We would love to work with you.
Remember that it is important to remove ashes regularly and properly by placing them, once they have cooled, in a metal container and storing them outside away from your home. Be sure to also have your chimney and fireplace annually cleaned. These simple maintenance steps are the best way to protect your home and loved one from the dangers of a house fire.