Static field route #19659

What do I do when acoustic liner was installed inside out?

Insulation, Liner, Vapor Barrier & Condensation⚠️ CHECK FIRSTField answer expansion

📖 Verified core answer

The coated liner face belongs toward the air stream. If raw fiberglass faces the airflow, it can erode, shed, and fail inspection.

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Field verification checklist

Identify the coated/black face before installing liner.
Confirm airflow side of the duct shell.
Pull and flip liner if raw fiberglass faces inward.
Check pins/adhesive after reinstall.
Inspect edges and seams before closing the duct.

Ask foreman

The liner is inside out. The dark coated side has to face the internal air stream to stop the air from tearing the insulation apart. Pull it out, flip the blanket around, and spin-pin it down right.

Text to foreman

Route options

A Correct prep/setup only if the fix is within your assignment and the approved method is clear.

B Hold and document if it affects safety, structural support, rated assemblies, airflow, access, tools, material condition, or another trade.

C Bring the journeyman/foreman the location, what you checked, and what decision you need before the crew loses time.

Do not do this

Do not leave raw fiberglass exposed to active duct airflow.

Why this matters

Correct liner orientation protects air quality, liner durability, and inspection acceptance.

Final verification

Use this as field training guidance. Final direction still comes from the foreman, approved drawings, project specs, manufacturer installation instructions, employer safety policy, pressure/material schedule, and AHJ/code requirements.

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