Question: Craig, I have a small woodstove with a Security pre-fab chimney in my basement. The chimney runs up through a closet on the first floor and out the roof. I would like to replace it with a coal stove. My chimney sweep says the chimney will turn into swiss cheese in a few years if I get a coal stove. Can you elaborate and make any suggestions? Answer: Coal contains sulfur, which can become quite corrosive if left in the chimney over the humid summer. In my experience, cleaning the chimney immediately after the heating season will greatly reduce any possible corrosion. Also, pouring a base (baking soda?) down the chimney while brushing should also help neutralize any acids. Lots of people with coal stoves use metal chimneys with success. In any case, it is possible that the life of the chimney will be reduced. If the chimney is larger than the coal stove outlet, you could like the chimney with a single wall stainless pipe.