Re: Wet insulation around chimney...
Does your furnace, by any chance, have a 3 or 4 inch flue pipe and forced draft? If it does , it should not have been dumped into a large chimney, it should a a pipe or flue liner the same diameter going all the way up through the chimney. The newer forced draft furnaces do not supply enough draft to flush the chimney. Because of that the hot moist air goes part way up the chimney cools off and the moisture condenses. However the amount of moisture your describing seems to be a bit high. I would suggest a chimney cap that cover the entire chimney punched out for the flue pipes. That would take care of the condensation and any leaks around the cap. In the mean time I would suggest you use rigid foam insulation around the chimney until the problem is resolved. Ridged foam would at least be water proof.
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