Expert: James Ball - 9/22/2009

Question
QUESTION: hi.. we built a house from scratch 18 months ago. We have 3 fireplaces but one has a gas fire in it. Our fireplace in the drawing room works perfectly. However our other firplace just continues to send out severe amounts of smoke into the room.. but not every time !!( 27 inches wide by 15 inches deep). The architect has had a look, the builder & the fireplace provider without success. There is a good distance between the grate & the flue ( 24 inches) comparable to the firplace that works. We have a cap on top of the chimney. It is a 2 story house. Can you help ? We have underfloor heating but it is not on at the moment & last night we lit a fire & the smoke was horrendous. There is one internal & one external door into the room.
Adrienne

ANSWER: I believed I answered this if not please respond to this
James

---------- FOLLOW-UP ----------

QUESTION: where is your answer ?

Answer
Welcome back Adrienne, What is happening is you are getting Negative Pressure in your home (house stack effect) that is hot air rising in your home (and getting out through the attic vents, doors, lights) your house is a better chimney than your chimney. Also kitchen/bathroom exhaust fans, cloths dryers and the boiler/furnace all take house air out of the house (mechanical negative pressure) your house needs make up air, perhaps an open window in the basement? Or stop the air from getting out the attic and other area.
Trail and error until you get this fireplace to work for you, maybe close off the room from the rest of the house to use it (close doors) try to open a window in the room with the fireplace and see if it makes a difference (it should work with no problems) once going close the window and use.
Or it could be dirty? I would have a local Certified Chimney Sweep (www.csia.org, there you can look up by zip code to find one near you) take a first hand look at what you have.
James