Our Company Blog

All About Dampers

With high temperatures at the beginning of November only scraping the high fifties in Seattle, the fall season is in full swing. Shorts and sandals are being swapped out for jackets and gloves, and everyone is looking ahead to winter and thinking of ways to stay warm. For some homeowners, part of staying warm could involve lighting up the fireplace or wood stove. That means scheduling the annual chimney sweep and inspection before using the fireplace too much. During this year’s annual inspection, ask the chimney specialist about the damper in your fireplace. The major responsibilities of this seemingly simple apparatus may surprise you.


The damper is a flap found at either the bottom or top of the flue, and it is generally made of ceramic or stainless steel to withstand the high heat of the fire. It moves using a pull chain, handle or latch, and its main function is to control air flow in and out of the chimney.

This simple mechanism is one of major contributing factors to the draft of the chimney. The draft is essentially the flow of air from the inside of the house, into the fire, and up the chimney. When a fire is lit, the hot air tends to rise because it is less dense than the cold air outside. The pressure differential creating by this initial burst of hot air creates the draft, which can be imagined as an upward “pull” of the air in the chimney. This force directs the smoke from the fire out of the chimney, and in turn, it pulls the highly oxygenated air from the house into the fire, which results in a hot, efficient fire. All of this physics and air flow comes down to how wide the damper is open. A too wide damper could take all the hot air right out the chimney, or it could deplete the oxygen levels to the point where the fire burns out. On the other hand, an overly narrow damper opening could cause the draft to go in reverse, essentially filling the house with smoke and eventually extinguishing the flame.

How the damper is positioned also affects the fire. A damper at the bottom of the flue, right above the firebox, is easy to see and open. However, it keeps the majority of the chimney cold when the fireplace is not in use, so starting the fire is much slower. The hot air has to push past much more cold air, and starting too large of a fire initially could result in a smoky house. Conversely, a damper at the top of the flue means the chimney stays warmer, so it takes much less time to start a large, hot fire. However, this damper position also makes it hard to keep an eye on the condition and the width of the opening of the damper.

In contrast to their relatively simple construction and mechanism, dampers actually play a huge role in the efficiency of the fire and in keeping the house safe and smoke-free. During your next inspection, be sure to check with the inspector to learn where your damper is and how to safely use it. If you live in the Seattle area, you can contact Pristine Sweeps to speak with a chimney professional.

Purchase and Properly Store Local Seasoned Firewood for the Best Fire

With summer a mere memory, fall has stepped in and taken over. Stunning reds, golds, and yellows decorate the landscapes, and crisp winds have everyone bundling up in their favorite fall jackets. In addition to raking leaves and sipping hot apple cider, homeowners are also looking ahead to heating their homes for the next several months. Many homes utilize wood-burning appliances like stoves and fireplaces. To make use of these units, it is crucial to have an ample supply of firewood fuel.


For a lot of homeowners, purchasing firewood is a hassle. They are faced with questions like where to buy the firewood, how much will they need to make it through the season, and what types of wood should they burn. Upon making all of these decisions, the next step is figuring out the best way to store the firewood.

If you chose to buy seasoned firewood, the wood has had a significant amount of time to dry, so all you need to do is keep it dry before you burn it. However, seasoned firewood is often sold at a premium because it is dry and ready to burn. For that reason, many choose to purchase “green” firewood, which simply means it was freshly cut and extraordinarily wet. Storing this green firewood properly is vital to burning a hot and safe fire this season.

The first step is to keep it far from your home. While thirty feet away is ideal, just store it as far as you can based on the space you have. The rodents, termites and other bugs that live in it may begin infesting your home if you store the wood too close. Avoid this risk entirely by simple keeping the wood farther away.

Next, stack your wood off the ground to allow air to flow under it and help it dry faster. You can do this easily with a wood pallet or by placing 2 x 4 boards on the ground before stacking the wood.

Covering your wood is vital to helping it dry before burning, especially in rainy Seattle. Try to keep the sides as open to air flow as you can to encourage quick drying, but always keep the top of the stack covered. Good covering options are plastic tarps and metal roofing sheets.

After a few months of being allowed to dry like this, you can have your own seasoned firewood without having to pay extra for it. Experts recommend burning wood that is only 20 percent moisture or less. This means only 10 percent of the weight of the wood is due to water. To measure this, look at the end of the wood to look for quarter inch “check,” or cracks. You may also opt to invest in a moisture reader that measures the moisture level just below the surface of the log. Burning an overly wet log results in a cooler fire, as some energy goes toward boiling away the water. It also creates a lot of smoke filled with dangerous chemicals like creosote.

If you have any questions regarding choosing and storing your firewood, contact the professionals at Pristine Sweeps of Seattle, Washington. These experts can also sweep and inspect the chimney of your wood-burning appliance prior to you lighting the first fire this season.

By Aaron Woodward | Tagged with: Tags: , , , , | Leave a Comment