Foam distortion in the attic is there a root cause?
suect
| Posted in General Questions on
The foam in my attic is looking different at the peak of the underside of the roof and I’m in search of the root cause.
I have used a dehumidifier to keep the humidity below 60% and have the mechanical fresh air controller set to allow 10 minutes out of every hour of air to come in with limitations on humidity at 55%. Currently bath fans are the only exhaust.
Too much positive pressure cause this to occur or humidity or possibly both?
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Questions:
1. What climate zone are you in?
2. What type of foam?
3. What does it look like? A picture might help.
Our home is in San Antonio, it is an open cell foam. I will send photos early tomorrow…not fond of the pull down steps.
Read this article and tell us if the symptoms fit:
https://www.buildingscience.com/documents/insights/bsi-088-venting-vapor
I think this may be it. What can I do in the foam attic to stop this?
Last year there was an open return only that was sealed and an opening around the chimney flue that was sealed. The changes occurred shortly after.
Some tell me my humidity too low as I try to keep the main level under 50%, possibly causing wood to shrink. One other person stated my humidity, if above 45% is too high.
Any thoughts on how to address this?