When creating or redesigning energy-efficient homes that are draft free, we need to consider there must be means for outdoor air to enter the house to operate the devices we use in them. A fireplace must pull air from somewhere to provide combustion air for the fire and allow an updraft for fumes to be pulled out, air must be supplied at an equivalent rate to replace the air leaving the chimney. homes that are air tight or have no means of circulatory air can prevent chimneys from operating properly, especially where other air-moving devices are being used such as furnaces, bathroom or kitchen vents, attic fans, clothes dryers, etc. Again, replacement air for these devices AND for the chimney may be entering through the chimney. It is possible to have cold air dropping down one side of flue while warm smoke or fumes are also trying to exit at the same time. Try opening the closest window to the fireplace to provide extra air for the fireplace AND make sure no other air-moving devices are being used in your home at the same time.
If your fireplaces once worked well and now do not, consider whether you may have made alterations that affect its ability to draw air, installing items such as weatherstripping, replacement windows, new siding, extra insulation, room additions, or new appliances can have an effect on the air cirulation and air pressure. High efficiency clothes dryers that dry clothes more quickly can use drastically more air to operate.
Chimney and fireplace professionals may be able to suggest alterations to improve or cure any smoking or malfunctioning fireplaces. If your new stove or fireplace is not working properly, have it checked by a pro for advice. But remember, using the best principles of design for a fireplace or stove installation may not be overcome by the design of the house and the way that air enters and leaves it. Simply put, we in the fireplace industry cannot solve smoking or draft problems in every situation.