Lowered Humidity in Attic and Shrinking Foam Insulation
We purchased a home in Texas last June.
After moving in we noticed mustiness and mold type odors that seemed to be increasing in the fall.
Last November we used stand alone dehumidifiers on the main level and attic. The humidity was between 55-65%.
Over several months we lowered the humidity to 45%. In the attic boards were beginning to crack and the foam began to shrink slightly. The attic dehumidifier was off while away for one week only to return to an attic at 65%!
In the spring the fan speed on our A/C was decreased from high to medium low, which caused a drastic shrinkage change in the foam.
I read that 40% to 55% is the ideal and 40% being the goal for the winter months.
Now it is winter our humidity is in the high 40’s and more shrinking of the foam is occurring. One contractor mentioned it’s the low humidity and another states humidity should not matter, yet another states it should be at 55% as it was more than likely, never below this before.
Our home feels chilly, and I wonder if there has been shrinkage of wood that would create gaps.
Any thoughts on what occurred, and if this can be corrected?
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