Why do I get a downdraught from my chimney?

If you notice occasional puffs of smoke coming from your flue into your home, you might be dealing with a downdraught. This occurs when air and smoke are pushed back down the chimney instead of being carried outside. It’s important to determine whether the issue is a downdraught or something else. If smoke flows continuously into your home, it’s likely not a downdraught but a different problem altogether.

A downdraught typically happens when smoke intermittently puffs into your home rather than exiting through the chimney. This can be caused by a chimney that’s too short, or if your home is surrounded by taller buildings or trees that disrupt airflow. Weather conditions, such as wind and temperature changes, can also contribute to downdraughts. Another potential cause is a flue that’s the wrong size for your fireplace. Ideally, the cross-sectional area of your flue should be about 1/10th the size of your fireplace opening.

If you suspect your flue is too small, you can temporarily reduce the size of the fireplace opening using sheet metal or masonry materials. However, for a permanent solution, it’s best to consult a professional chimney service. They can assess the issue and may even create a custom device to adjust the fireplace opening. On the other hand, if your flue is too large, it can reduce your chimney’s efficiency. In this case, installing a properly sized flue liner can help resolve the problem.

Blockages in the flue, such as bird nests, debris, or creosote buildup, can also cause downdraughts. To avoid these issues, it’s a good idea to have your chimney, flue, and fireplace inspected and cleaned by a professional before winter arrives. This ensures everything is in good working order before you start using your fireplace regularly. Addressing any problems early can save you from dealing with bigger issues during colder months.

In some cases, lighting a fire and warming up the chimney can help alleviate a downdraught. Additionally, if you have other appliances, like a tumble dryer, venting into the same flue, this could also cause issues. A professional can check for leaks or cracks in the connector pipes to ensure proper ventilation.

At Master Clean, we have the expertise and experience to help you diagnose and resolve any chimney-related problems. Whether it’s a downdraught, flue sizing issue, or blockage, we’re here to ensure your fireplace operates safely and efficiently. Don’t hesitate to reach out for a thorough inspection and cleaning before the winter season kicks in!