Below are answers to some of our most asked questions. If you still have questions, please feel free to contact us.
The most common causes of masonry and manufactured metal chimney fires are:
- improper installation
- improper maintenance
- improper use of the chimney
The best way to prevent a chimney fire in your home is to:
- Make sure that the chimney was installed correctly — The chimney should not be too close to wood framing or insulation. The chimney or metal flue pipe should pass through the ceiling properly.
- Check routinely for any structural damage to your chimney. For metal chimneys, look for corrosion or rusting of the chimney’s inner layers. Also look for buckling of the inner seam or collapsing of the inner lining. For masonry chimneys, look for cracks in the brick and the tile inner lining of the chimney. If your chimney does not have an inner liner, it is imperative that you get one before using your fireplace.
- Check frequently (as often as twice a month) for creosote and soot build up. If you see it, hire a chimney sweep to remove it.
- Keep up with annual chimney inspections and cleanings. A professional inspection and cleaning will help keep everything clean and in good working order.
Here are a few things to check if you’re experiencing issues:
- Is your damper fully open? Everybody forgets to open the damper from time to time. Many dampers also cease to fully open because of water damage or soot buildup behind them on the smoke shelf. A good professional cleaning can usually solve this problem.
- Is your firewood green or wet from rain or snow? Remember, the main reason your fireplace works at all is the heat inside the chimney. If your wood is not dry and well seasoned, it will result in more smoke than heat, and there simply may not be enough heat for the chimney to work properly.
- Is your chimney dirty? The gradual accumulation of soot can seriously affect the way your chimney performs. Thick layers of soot can physically restrict the flue so that there is no longer enough free space to vent the fireplace properly — but even as little as a 1/4″ to 1/2″ inch buildup can make more of an impact than you might think. Consider that a 1/2″ buildup will restrict the air flow by 17% for a typical masonry fireplace chimney, and by a whopping 30% for the average prefab. Birds and small animals also think your chimney looks like a hollow tree in which to set up house. Sweeps often find chimneys literally packed full of leaves, twigs, and baby animals. The solution of course is a good cleaning and a chimney cap.
- Is your chimney tall enough? To function properly, the chimney should be at least 10 or 12 feet in overall height. Where it projects above the roof, the chimney should be at least 3 feet tall, and at least 2 feet higher than anything within 10 feet of it — including other buildings, trees, etc. If your fireplace smokes because your chimney is too short, the problem is usually worse when the wind blows. But don’t worry – we can extend your chimney!
- Is your flue large enough for the fireplace opening? There are many variables that can affect this, including overall chimney height, how warm the flue stays, throat configuration, etc., but the basic rule of thumb here is that the area of the fireplace opening can be no more than 10 times the area of the flue (12 times for round flues). An undersized flue simply can’t handle the volume of smoke produced, and some of it will spill back into the room. Since there is no practical way to make the flue size larger, the solution may be to make the room opening smaller with metal smoke guards or some creative masonry work. In fact, there are now some pre-manufactured refractory firebox retrofits that work well with a 15 to 1 ratio, and deliver twice the heat of conventional fireboxes.
- Is your home too airtight? Fireplaces require large volumes of air to burn efficiently. Visualize a 12″ x 12″ column of air rising up your chimney and exiting the top while your fireplace is working (but don’t visualize your heat bill!). This air comes from inside the living area and must somehow be replaced to keep the fire going. With modern energy efficiency concerns, most houses have been carefully insulated and weather-stripped to keep out the cold drafts. But an undesirable side effect is that there is often nowhere for all that air leaving the chimney to get back into the home. This can cause fireplaces to burn sluggishly and smoke. A temporary solution is to open a window to let in a little make up air, preferably on the windward side of the house. But not having enough air in the home can also lead to very dangerous carbon monoxide buildup, as your fireplace and furnace must compete for combustion air. Our team can help you quickly find a permanent solution to help protect you from this threat.
Is there a return air grill in the same room as the fireplace? As the fireplace consumes air and cold air moves into the house to replace it, the furnace is likely to come on. When the furnace comes on, air is drawn into the return, competing directly with the needs of the fireplace. If this is the cause of your fireplace troubles, we can find a solution!