I’m familiar with the correct way to install a vapor barrier but I’ve never seen this
A layer of fiberglass batts with the vapor barrier down towards the crawlspace with another layer of fiberglass insulation. Am i safe top assume this is wrong?
The insulation “facing” (paper or foil vapor retarder) should always face the warm side of the structure it insulates. Excessive condensation can result otherwise, but how much of a problem that is depends on the climate zone the house is in.
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Yes, like Kenton said…wrong.
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To better elaborate what Kenton said…
A vapor barrier should always be the component closes to the warm side of the structure, so in your case, you have two seperate layers of insulation and a VB. The two layers of insulation should be “touching” each other with the VB at the sheathing on the warm side. The first layer of insulation was incorrectly installed with an added layer added over it. In effect, moisture will become trapped within the center of the insulation mass.
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As Kenton started and others supp
Also pay attention to:
So what is heat that constitutes the “warm side”?
Well there are two types of heat, latent and sensible. One you can measure with a thermometer and one you can’t. Moisture is “latent heat”. There is a huge difference between Arizona and Florida. If you primarily run A/C over Heat, and there is a damp basement or crawlspace, which is the warm side?
Doing it the “Right Way” is not always the best way. Building Code and Construction practices are not always right. Inspectors in high humidity regions often see fiberglass bats falling from the floor above. That’s because it is loaded with water.
Humidity in fiberglass bats increases the conductivity of the Insulation lowering it’s R-Value significantly. Is that what you want when you call this out to turn it over because someone said it’s the “Wrong Way”?
You can argue this all day long, but I have had to deal with this hundreds of times performing Building Science Assessments that caused significant damage to structures in Tennessee (not home inspections).
Hot goes to Cold. Hot has more moisture. Cold (below dew point) causes condensation. Condensation causes increased heat transfer rate, rot, mold, insect infestation, and indoor air quality problems.
Just a though for your consideration…
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…AND Oregon, which is where the OP is based. I lived in Washington state for 20 years, and am very familiar with weather patterns in Redmond,OR. My reply was based upon this information.
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Yup, my daughter lives out there…
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