Fan bracing creates a metal vibration bridge across a sound trap

A sound trap cannot do its job if vibration bypasses it through rigid metal. Separate fan, flex connector, silencer, and supports per the approved acoustic detail.

Stop if

• The fan/silencer setup has rigid metal bracing crossing the acoustic break. I checked the vibration path. Do you want the bridge removed and the flex isolation restored per detail?

Watch out

• Do not brace across an acoustic break and accidentally short-circuit the sound treatment.

Check

• Identify the vibration path from fan to duct/silencer to structure.
• Look for continuous angle, strut, screws, or bracing crossing the flex/acoustic break.
• Confirm required flex connector/vibration isolation detail.
• Remove or revise rigid bridging only with direction.
• Retest noise/vibration after separation.

Steps

• Identify the vibration path from fan to duct/silencer to structure.
• Look for continuous angle, strut, screws, or bracing crossing the flex/acoustic break.
• Confirm required flex connector/vibration isolation detail.
• Remove or revise rigid bridging only with direction.
• Retest noise/vibration after separation.

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