Causes of a Smoky Chimney
Smoky Chimney Causes
If smoke is backing up into your home, here are the most likely causes, in no particular order.
Issues With Construction
As noted, the chimney and fireplace must be sized to complement one another. When either was built with the wrong dimensions, smoke can draft poorly. A builder’s rule of thumb is 10 square inches of firebox per inch of flue.
Cracked Chimney Liner
When a chimney liner is cracked or decayed, it opens a channel for smoke to go somewhere other than straight up the flue. Rough, damaged liner areas can trap creosote and cause it to accumulate, further slowing down the draft.
Damper Not Open
Make sure your fireplace damper is able to open completely.
Clogged Chimney Cap
If the mesh sides of your chimney cap are clogged with soot, creosote or debris, smoke will have a hard time getting out.
Debris or Creosote Blocking The Flue
Outside debris, animal nests and dead small animals can narrow the flue and make smoke back up. Excess creosote, which forms when smoke condenses in the flue, can build up to the point that it shrinks the air passage and keeps smoke from rising.
Cold Flue
Cold air is heavier than warm air. If you start a fire with a cold flue, the warm smoke may not be able to move through the denser air. Solutions could include chimney insulation, a top-mount damper and warming up the flue air with a lit, rolled-up newspaper or blow-dryer.
Negative Air Pressure In The Home
HVAC systems, along with bathroom and kitchen exhaust fans, can lead to a smoky fireplace by pulling air out of the flue. An extremely airtight home may not provide a sufficient volume of drafting air.
Damp Firewood
Damp, unseasoned wood creates a lot of smoke – often too much for your chimney system to handle. You should burn only seasoned firewood that has had at least six months to dry out.
Smoky Fireplace Solutions
Anderson’s Chimney & Masonry Service addresses smokey fireplaces by starting with a chimney and fireplace inspection to determine exactly what’s causing the problem. We can then get to work to fix it the right way.
Our certified crews work throughout York, PA, New Cumberland, PA, Camp Hill, PA, Hershey, PA, Lancaster, PA, Carlisle, PA, Middletown, PA, Linglestown, PA, Lebanon, PA, Columbia, PA, and other Pennsylvania communities.
Speak with a chimney and fireplace expert by calling (717) 975-3526. You can also use our handy contact form.
National Standards
As certified sweeps, we are held to national standards of the NFPA. NFPA 211 for wood burning, NFPA 54 for gas appliances and NFPA 31 for oil appliances. All of our work is always conducted professionally and in compliance with these and any other local government codes that apply. Our professional opinions will be based on our experience and education.
