Is an airtight chimney cap a mold hazard?

Our house is a one level bungalow/rancher with an unconditioned attic.  I’ve been gradually doing things to improve air tightness and was considering an airtight chimney cap — the spring… Our house is a one level bungalow/rancher with an unconditioned attic.  I’ve been gradually doing things to improve air tightness and was considering an airtight chimney cap — the spring…Read MoreGreenBuildingAdvisor