In order to function properly and safely, each part of your fireplace and chimney system should be installed or built correctly. Local building codes must be followed exactly when constructing a fireplace and chimney, and the height of your chimney is included in these codes. According to the online resource for homeowners and chimney professionals, Chimneys.com, the builders must follow the National Fire Prevention Association Standards 211 as well as the requirements set by the International Residential Code. Both of these state that a chimney must be at least three feet higher than the high side of the roof it exits. The chimney must also be at least two feet taller than any trees, dormers, and roofs within ten feet. If the chimney does not meet these height requirements, problems will occur. Ashbusters would like to share with you why your chimney needs to a specific height and some of the problems that can happen with a chimney that is too short.
Why does my chimney need to built to specific height requirements?
The main issue with chimney height has to do with draft. If the chimney is not tall enough, your fireplace will suffer from inadequate draft and not function properly or safely. The column of rising hot gases inside your chimney will not be able to develop a safe and adequate draft. A chimney that is too short cannot vent correctly and can become a serious fire hazard to your home.
I am having problems with smoke entering my home through my fireplace. Could this be cause by inadequate draft?
One of the biggest problems caused by inadequate draft from a too short chimney is a smoky fireplace. If your chimney is located at the end of your house and is not taller than the house, your house will act like a chimney and pull air upwards. When this happens, you are at risk of the “stack effect,” which is when smoke gets pulled back into the house from the fireplace when a fire is burning. When there is no fire, this effect can pull odors from the chimney into your home.
What other problems can be caused by inadequate draft?
Not only does inadequate draft push smoke back into your home, it can encourage soot and other smoke residue to build up on the walls of your chimney, which could possibly start a chimney fire. The most serious problem caused by inadequate draft can be deadly. The lack of a proper draft leads to incomplete combustion and can produce poisonous carbon monoxide gases. Additionally, there is a greater risk of this carbon monoxide leaking into the home because of a backdraft. As this toxic gas is odorless and tasteless, it is impossible to know if you are breathing carbon monoxide unless you have a detector installed in your home to alert you of this danger.
Have questions about the height of your chimney? Contact Ashbusters to schedule a visit to see if your chimney is tall enough to function properly and safely.