Insulation Thickness for Condensation Control

What insulation thickness does spec require for condensation control? Is vapor barrier required with this insulation?

I'm checking insulation thickness for condensation control at [location]. I found duct wrapped with insulation of specific thickness, or spec calling for specific R-value. What insulation thickness does spec require for condensation control? Is vapor barrier required with this insulation?

Stop if

• Hold point on insulation thickness for condensation control: I have the location, photo, drawing/detail, and what was checked. Who should verify before this gets cut, covered, lifted, sealed, energized, or signed off?

Watch out

• Don't install without vapor barrier in conditioned spaces. Don't use wrong tape type. Don't leave gaps or tears unrepaired.

Check

• room/grid/area
• photo of condition
• drawing/detail
• manufacturer/model if visible
• what I already checked

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