The inteior plaster wall on my chimney becomes damp and efflorescence appears after every rain storm and when snow is melting in the spring. I am hoping someone can help me figure out a) how the water is getting in, and b) how to stop it!

Some background--My chimney was rebuilt from the roof up and a new roof installed about 2 years ago. The house was build in 1900, and the chimney is otherwise original (fireplace was removed 50 years ago) and now just serves to vent the boiler & water heater. I checked the flashing and it seemed fine. Both the roofing contractor and the chimney contractor double checked the flashing and also thought it was fine (but added a little caulk for good measure). The chimney contractor then added a cap over the entire chimney to prevent water from running down in the chimney, as well as a cap over the vent. End result-- the wall is still wet after rains and efflorescence continues to form. The contractor seems perplexed.

 

http://homeenergy.org/archive/hem.di...99/990915.html

Perhaps an inspection by a certified chimney specialist could help you solve the problem.