Frost and Condensation on Exterior OSB Walls…In brand new construction
My wife and bought a new construction home in northern New Hampshire in August. It is a split level and the lower level has a combination of grade to ceiling frames walls as well as walls with ~4 foot concrete knee wall and then framed wall. Pictures are attached to help make sense of my description of the space as well as photos showing the extent of the water/mold. This space was never finished and left with exposed R19 backed fiberglass insulation.
In prepping for installing drywall, our contractor noticed significant moisture behind the insulation. Further investigation relieved extensive moisture, frost and the beginnings of mold on three. We open a small portion of two upstairs walls and found the moisture extends to the finished part of the house.
I understand that this type of wall construction – vinyl siding – tyvek – OSB – fiberglass, can result in condensation. My question is – is this normal and to be expected for a house that is less than 9 months old? Is this the fault of the builder? What steps are necessary to remediate and prevent future condensation?
Replies
Do you know if there was any temporary heating used once closed in?
Basement or crawl?
There is radiant heat in the ceiling for the upstairs. From the time we moved in in august until a few days ago, the radiant was exposed. Other than that there was no additional hearing.
New construction emits a lot of moisture for the first winter at least. Fiberglass insulation with no air barrier over it allows a lot of that moisture to pass through to the wall sheathing where it can condense.