Expert: James Ball - 1/31/2010

Question
I have a house built in 1962.  The house has two fireplaces.  One is on the main flore and one is in the basement.  They must share a chimney and some point in the construction because whenever we use the fireplace on the main floor, the basement becomes smokey.  We have tried building fires with the basement fireplace flue open and closed to see if that makes a difference.  Both fireplaces seem to be in very good condition and were expected five years ago when we moved in.  What could be the reason for this problem?

Answer
Hello Tamera, what is happening is you are getting Negative Pressure in your home, if 10 gallons of air is going up the chimney per minute then it needs 10 gallons of air per minute and it will pull the air from the path of least resistance from your home and in most cases it will pull that air down an other flue and with it smoke/odor the house needs make up air. Maybe open a window in the boiler/furnace room? Maybe extend one flue or the other to make it taller, add a top mount damper cap,
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 they should be able to help.
Hope this helps
James