Solving a Chimney Draft Problem

With the official start of winter just a few days away, most homeowners with fireplaces or wood stoves have at least burned a couple logs. Fireplaces are not all fun for everyone though. Perhaps you do everything right – the annual sweep and inspection, asking all the right questions, burning all the best wood – and you still cannot seem to build a strong fire. Stop feeling bad because it may not be you. Your chimney may have draft problems.


Chimneys work because hot air rises. The hot air produced by the fire has a low density, so it moves upward through the chimney. Most fires are burned during the colder months of fall and winter, so the hot air from the fire usually meets comparably cold air from the outside sitting in the chimney. When the hot air meets the cold air, the difference in pressure between the two portions of air creates a vertical pull that draws air up the chimney. This movement of air is known as the “draft,” and it pulls air rich in oxygen from the house to help fuel the fire, and then the smoke and other harmful gases safely escape through the chimney. If the air fails to flow this way, the issue is called a draft problem.

The most common draft problem homeowners experience is a chimney that is too large for the firebox. Old fireplaces in particular often have oversized chimneys that result in draft problems. A wide chimney gives the hot air more room to spread vertically, which then slows its vertical progress. When the hot air moves more slowly up the chimney, the upward pull becomes weaker. Thus, the draft weakens and the air moves inefficiently through the system. Creosote also condenses easier when the flue is too large and the draft is too weak. This can be deadly as creosote is highly flammable and can cause a chimney (or house) fire. Signs of this problem include a small, cool fire or even a fire that refuses to stay lit. Fortunately, this problem can be easily remedied with the help of a chimney specialist. With a few measurements, the specialist can determine the proper flue width the fireplace requires and install a flue lining with the corresponding size.

Another cause of draft problems is a short chimney because the draft is more powerful in a taller chimney. Short chimneys are common in aged bungalows and ranch style houses, and they can lead to cold, smoky, or inconsistent fires. Although adding height to the chimney is not a welcomed expense, it can save money in the long run by preventing a reverse draft in which the cold air from the outside actually flows into the house.

You should not have to worry about draft problems while you simply want to enjoy your home and fireplace. If you live in the area of Aurora, Illinois, get in touch with Pozzi Chimney Sweep for a professional consultation. These experts can diagnose your draft problem and guide you in making the most informed decisions when addressing it.