Our home was built 3 years ago which consists of a masonry (stone) chimney. This is the first season which I am burning wood in our stove (only burned a dozen times the previous year) which is located in our basement. 2 months ago I noticed a horrid smell coming from our basement. To make a long story short, the smell was coming from water that was in our chimney clean out. The water was at the very top of the clean out which is about 6” deep. I’m not sure how long it was there but it had a very unpleasant odor. We never had a cap installed on the top of our chimney. I thought this is how the water was getting in and over 3 years of rain was enough to fill the clean out. Last night I rechecked the clean out and again it is filled to the top. Not sure who to call to look at this problem. My chimney is not insulated. Could that much condensation occur that it would fill the clean out? Is the water getting in from not being properly sealed around the roof? Could it be coming in below ground? I know it is going to be hard to tell without seeing it but I’m perplexed on who to call to look at this issue. Any help is appreciated.