Why Does My Fireplace Smoke?

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Why Does My Fireplace Smoke?

Why Does My Fireplace Smoke?

The only purpose a chimney serves is to draw smoke and other particles from a fire in the fireplace below up and out of the house.  It sounds simple enough, but There are many reasons that a chimney may not be properly pulling the smoke from a fire up and out of the house as effectively as it should.  

Construction of the firebox, layout of your home, what and how you are burning materials (type of wood), and height of the chimney and flue all affect the efficiency of the chimney.  If the smoke doesn’t get to the top of the chimney as quickly as it should, it will spill over into the room.  

The most common problem when a chimney wont vent properly is a damper that is not open, or is somehow blocked, even partially.  An old rusty damper just may not open fully.  Creosote could have built up in the chimney, blocking air-flow.  Or an animal may have nested in the chimney.  Annual inspections and sweeping will prevent these causes of smoke in the house.

If the chimney doesn’t seem to vent well when you first start the fire, it is likely because the chimney and flue are cold.  If you burn a fire irregularly in the winter, the flue and chimney may have time to get cold – that is, a block of cold air will settle in the chimney.  Cold air rises slower than hot air.  When the initial smoke from the fire tries to escape up the chimney it is met by this wall of cold air.  Until that cold air is heated through and also rises, some smoke may spill in to your room.  You can prevent this by heating the chimney before you start the actual fire.  Simply light a bit of newspaper and hold it up in the damper area of the chimney.  Once the cold air is out of the chimney, it should have no problem venting the smoke.

What you burn also affects the effectiveness of the chimney in dispelling smoke.  Always burn wood on a grate that is placed as far back in the fireplace cavity as possible.  Having the wood on a grate improves the combustion process and also brings the smoke higher in the smoke chamber, giving it a better chance to vent properly.  Unseasoned or green wood typically creates a VERY smoky fire.  Always burn wood that is properly seasoned, and dry.  

Lastly, it is important that the opening of the firebox is proportionate to the size of the flue it is attached to.  Newer construction should have adequately high fireboxes.  According to building codes, a chimney needs to extend at least two feet higher that anything within a 10-foot radius.  This can be problematic particularly if a house has been remodeled and a fireplace and chimney are added.  

Consult with a licensed professional chimney sweep if you have any issues with a smoky fireplace.  Call Chim Chimney today.  They have the knowledge and experience to solve your problem as cost effectively as possible.  

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