Old Houses with Fireplaces May have Chimney Safety Issues
There is undeniable charm to older homes that seems to rarely be replicated in new ones. The character in houses built decades ago provides appeal that many buyers can hardly resist. When an old home is complete with a fireplace, however, buyers should be aware that older chimneys may be a safety hazard.
Deterioration – Bricks made in centuries past were of a much higher quality than modern-day bricks, and the reason is in the method of firing them. While bricks on very old homes may be incredibly durable, they eventually begin to deteriorate. A chimney in disrepair is vulnerable to moisture, which can lead to damage inside the home. Another situation that arises and adds to the moisture problem is that the mortar holding the bricks together wears out much more quickly than the masonry and needs to be replaced. If you address chimney problems early, a procedure called “tuckpointing” could save you the trouble of rebuilding a leaning or collapsed chimney. The beauty of tuckpointing, besides the fact that it is a lot less expensive than a re-build, is that it refreshes the entire look of the chimney and provides renewed structural integrity, as well.
Pyrolysis – The distance between combustible parts of a home and the chimney and fireplace was not always considered a safety issue. It has been discovered, however, that the proximity of combustible materials to extreme heat is very important because of the potential for pyrolysis. If ignitable materials are exposed to temperatures of 212°F or higher for prolonged periods, over time, the combustibles slowly dry out, break down chemically, and finally ignite. Only oxygen and heat are required for pyrolysis to occur, and the materials can burst into flames, even without being directly exposed to a fire. Without a chimney liner, all of the parts of the home that are close to the chimney could be in the process of pyrolysis.
No Chimney Liner – Sometime in the 1940s experts in fire safety in the U.S. concluded that chimney liners are an absolute necessity, to prevent house fires. If an old home pre-dates mandatory chimney liners or if the builder ignored the requirement, there may not be a liner in the chimney. Of all of the chimney components, which are numerous, none are more important than the chimney liner for providing protection against an out-of-control house fire. Read more about pyrolysis below, which is caused by the lack of a chimney liner or a damaged flue. But there are other dangers, as well, when a chimney is not lined:
- Without a chimney lining, there is a greater possibility that toxic fumes such as deadly carbon monoxide could enter the home.
- The drafting in an unlined chimney is not as effective, and drafting is essential for a chimney to operate properly. The narrowing of the chimney which the flue accomplishes is part of what improves the draft as well as a fire’s heating efficiency.
- Be very sure to check for a chimney liner because most homeowner insurance policies will not cover a house fire if the house fire originated in a chimney that was not lined.
Before you light the first fire in an old home, be sure to have it inspected by chimney technician, who can provide assurance either that the fireplace is safe to use or that repair of some kind is needed. By taking this precaution, you can help to ensure the safety of your family and the further enjoyment of your wonderful old house.