This is called the “syndrome of cold air discharge”. This reverse circulation can be attributed to the negative pressure inside the house caused by the operation of an exhaust fan like the fan from a stove. Most of the time it is caused by the combined effect of the outdoor chimney and the wood stove installed in the basement.

When there is no fire in the stove, the air in the chimney gets cooler and reaches the same temperature as the air outside, which makes it hard for the chimney to draw air. The slight negative pressure that prevails in the basement that is caused by your house’s air draught is enough to pull the air from your chimney thus making the smoke come out thru all the openings from your wood stove or fireplace.

To help prevent this problem, when you start your fire, slightly open a window which is located on the same floor as your wood stove or fire place, to allow the wind to come in to balance the pressure. And then you heat the base of the chimney with a hairdryer, torch or anything else that does not produce smoke. Once you notice that the draught seems to be efficient you can light you fire and close the window.

If ever the problem persists, you should contact a certified chimney sweeper. Either your chimney is not waterproof anymore or it has a wind repression problem.