Why does my house smell smokey?

There are many reasons why your house may smell smokey: One of the main reasons is location of your chimney. If your chimney is located outside of the building (i.e. on an outside wall of the house) this may be the reason. Let me explain. A house typically has all windows and doors closed. This leads to two different pressure zones. The upper part of the house will be filled with warm air (+ air) which will be pulling upward and the lower part of the house will be filled with cold air (- air) which will be pulling downward.

See Figure 1

If you have a fireplace located on the second floor, chances are it will draw efficiently. That part of the house is filled with warm, upward pulling air. If you have a fireplace located in the basement, chances are it will not work because you are dealing with cold, downward pulling air (First floor fireplaces can go either way). Now if you smell smoke during the fire, after the fire, or when the air conditioner is on, there is a good chance your house is losing positive air (like letting air out of a balloon). The house has to make up for this loss of air through whatever opening it can find. In this case, the opening is your fireplace. Example: If you leave a second floor window open, the house will act better as a chimney then the chimney will (See Figure 2).

The exact opposite is true also, if you leave only a basement window open, the house will have more positive pressure in it (See Figure 3).

Many things in your house can affect this pressure. Any breech in the ceiling level can be a problem. An attic hatch, recessed can lights, bathroom exhaust fans without baffle, unsealed windows, and air conditioning ducts coming out of ceiling are typical causes of the smelly problem. In the basement the same problem can occur. Look around the 4” sewer stack as it is going through the first floor and make sure it is sealed properly. Look around the masonry chimney and any other thing that may be penetrating the first floor that goes up to the attic. If any of these items has a clear shot to the attic, the basement will be continually loosing air and can be giving you this smelly problem.

“How can I tell if any of these items are happening in my house?”

Generally there is one main thing to look for: cob webs. Cob webs are not caused by spiders, they are caused by continual air flow of warm to cold air or cold to warm air. So, if you see cob webs around your attic hatch, there is a strong possibility that you are loosing heat out of your house continually and your house is acting as a chimney. The smell or smoke coming down the chimney is a result of your house loosing too much air from the unsealed attic hatch. That air has to be replenished because your house is not going to implode, and so it is going to reenter the house whichever way it can. Since there are no windows open, it is going to come right down the chimney and give you the smell. No one knows your house better than you. Look to find what ways air can be leaving your house. It is generally a simple and inexpensive problem to fix. Test A good test you can perform yourself is get a cigarette and a strong flashlight. Make sure your house is closed tight for at least a few hours before you do this test. Light the cigarette and go around the house testing those areas I described above and any others you can think of that apply to your home. Let the smoke linger around those areas and hold the flashlight in a manner in which you can easily determine if smoke is leaving your building . If you do not want to perform this test on your own, we would be happy to come out and give you a consultation.

Chimney Drafting Problems Solved

Smoke Stacks, Inc. can solve your chimney drafting problems, whether it be from pressures issues to bad chimney liners (Flue Tiles) or chimney sizing issues.

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