You know you have chimney drafting problems if you see smoke coming back into your home rather than going up and out of your chimney. There’s no one answer to solve this problem and there could be numerous reasons behind the issue.
The first golden rule is to have a properly-installed wood burning stove or fireplace, which meets current standards. However, this isn’t a guarantee that your appliance will perform as expected. The size of your chimney also plays a critical role. Also, the firebox and flue must be the right size and properly installed for effective drafting to take place. Most wood burning stoves need a chimney flue with a diameter of six inches, and most manufactured zero clearance wood burning fireplaces need a chimney with an eight or ten-inch diameter.
Your chimney design also plays a role in your chimney drafting. To effectively escape, smoke needs to go straight up and out. So any bends, elbows or offsets can be a problem and lead to drafting problems. Therefore, straight chimneys are more effective. Furthermore, chimneys built on the outside of a house are typically very cold and need more time and to warm up the flue for effective drafting. When thinking about fitting a prefabricated metal chimney to your home on the outside, be sure it’s enclosed and insulated to help minimize chimney drafting problems.
Negative air pressure can also lead to drafting problems, especially in more recent homes. Today’s homes are tighter in construction and there’s less air to replace the air consumed during combustion. The places that suffer most from negative pressure are basements. Also kitchen fans, clothing dryers, and even vent fans can also cause your drafting problems when they’re in use.
Finally, external factors can play a role, including the design of your roof, trees near your chimney, high prevailing winds, and even where your home is situated.
Given the many factors that play a part in chimney drafting, it’s best to get a professional chimney technician to diagnose the problem. They’ll be able to find out what’s going on and offer you remedial options.