'Chim-chiminy' stereotype reconsidered
Q. We have a disagreement between a home inspector and a plumbing contractor over a chimney issue in our attic. The people who are buying our house hired a home inspector. He said the outer metal wall of our fireplace chimney is venting inside the attic, rather than above the roof.
We were having some plumbing repairs done, so we asked our plumbing contractor to take a look. He said the chimney looks fine, but the home inspector says it should be inspected by a professional chimney sweep. That seems like a needless expense, to hire someone whose job is to clean out chimneys. What is your advice?
A. When issues involving fire safety arise, "better safe than sorry" should be the default position. If the outer wall of the chimney flue terminates inside the attic, that is a serious issue that is not within the professional scope of a plumbing expert. A faulty diagnosis of this condition could result in a roof fire, and that risk is more serious than the cost of a professional chimney inspection.
Most metal chimneys consist of two or three sheet metal shafts, one installed within the other. The purpose of a multiple-wall chimney is to prevent the outer surface from becoming so hot that it can ignite the roof framing. The air between chimney walls can be extremely hot and therefore must vent into the open air above the roof. When the top of the outer chimney wall terminates inside an attic, heated air can scorch the wood framing to the point of combustion. Issues of this kind should be addressed by a qualified specialist, such as a certified chimney sweep.
The chimney sweep profession is among the most taken-for-granted of all building-related trades. People tend to think of sweeps as mere cleaning crews with top hats, long-tail coats and sooty faces. This Mary Poppins stereotype is an unfortunate misrepresentation of a highly specialized profession.
A qualified chimney sweep is a knowledgeable technician, possessing an array of skills essential to the construction, installation and repair of all types of wood- and gas-burning fixtures and equipment. A sweep's overall knowledge is unique, encompassing fire safety standards beyond the sphere of other building trades. In addition to specific installation and repair skills, a chimney sweep is proficient in the legal requirements set forth in the National Fire Code and is familiar with safety specifications affecting all types of fireplaces, inserts, wood-burning stoves and gas-log systems.
Plumbing contractors, regardless of competence and expertise in their own field, are not chimney sweeps and should not venture opinions related to fireplace safety. This is particularly true when one considers the professional liability a contractor undertakes when rendering such opinions. If your faucets were dripping, you wouldn't call a brick mason. If your feet were hurting, you wouldn't see a dentist. So why would you ask a plumber to evaluate a fireplace chimney?
When chimney conditions are suspect, the services of a chimney expert are imperative. A proper evaluation could save your home and possibly someone's life.
• To write to Barry Stone, visit him on the web at www.housedetective.com, or write AMG, 1776 Jami Lee Court, Suite 218, San Luis Obispo, CA 94301.
© 2016, Action Coast Publishing