What happens when Tyvek goes uncovered too long?
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I am a resident in a new apartment building in SC. I read the article on Tyvek and have reviewed that Tyvek has between 4-9 months to go uncovered before it expires. It has been 6 months, and the outside of our building is for the most part finished but has large areas of uncovered Tyvek. Recently my roommate and I noticed that at the bottom of our large windows we found large sums of puddled condensation and mold growing. Is this a result of the Tyvek being uncovered? We are not the only residents to have found this problem. If this is a result of expired Tyvek, what are the steps that need to be taken by the apartment building? Recover with new tyvek and cover with the final layer of material or will they have to take efforts to clear the mold?
Thank you for any help!
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Replies
Condensation on windows is most likely to be a symptom of high indoor humidity, poor window performance or both.
When exposed to ultra violet portion of sunlight sunlight the polymers in Tyvek break down a bit and become weaker, making it more prone to tearing or crumbling. If it's falling apart there may be higher moisture content in the exterior sheathing, but that would not be the cause of copious condensation on/under windows.
Lindsey,
I agree with Dana Dorsett: condensation on cold windows is not caused by exposed Tyvek. Either your interior relative humidity is too high, or your window panes are too cold.
Here are links to two articles on the problem:
Rating Windows for Condensation Resistance
Preventing Water Entry Into a Home