> In 1989 my grandparents built a home ... and carefully vapor-sealed the entire house
In the upper Midwest there were a number of homes built this way in the 80s/90s. 10-15 years later they all had black mold (nasty health hazard) growing in the walls because moisture couldn't escape from the house. All homes are now required to have air-to-air heat exchangers for this reason.
In the upper Midwest there were a number of homes built this way in the 80s/90s. 10-15 years later they all had black mold (nasty health hazard) growing in the walls because moisture couldn't escape from the house. All homes are now required to have air-to-air heat exchangers for this reason.