Mold appearing in a recently spray foam insulated room
Approxiamately 1 year ago, I was involved in a home basement renovation that included spray foaming the headers throughout the basement as well as insulating all the exterior walls(2 out of the 4 were exterior) of a converted storage/cold room(appr. 5’x 12′. In the last month or so, the home owner discovered mold along the entire length of the baseboard and part of the way up the wall, on the longest of the 2 foamed exterior walls, approx. 12′. The ext. walls have about 4-4.5″ of closed cell insulation and there was also a heat vent installed, dropped to just above floor level. The ceiling is not that of a typical cold room where the porch is above rather it is the floor of one of the interior rooms on the main floor, so I can’t see how this room is any different than the rest of the basement. The other baffling thing is that the door is left open all the time and there has been an oscilating de-humidifier running just outside the room(to my understanding it runs all the time). There is also a new window installed in the room that is energy star rated so the room is pretty air tight and not in darkness all the time. I am looking for any ideas on why mold would be appearing. My only guess is that the floor, which is tile on concrete, is a source of cold for condensation to happen. I’ve worked in many basements however and have never seen this to be an issue. I would like to be the hero here and offer my client an answer and a solution.
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