Vibration Isolation

[GTrinh97]

I'm currently researching vibration isolation methods for a residential project where a rooftop mechanical unit is supported by wood framing. I’m curious if anyone has dealt with a similar setup and can share their experience.

1. Would it be more effective to isolate just the equipment base, or the entire platform supporting the unit?
2. If the structural framing is experiencing noticeable vibration, is it appropriate to place isolation pads between framing elements (e.g., between a wood column cap and a girder or beam)? Or would that compromise structural integrity?

 

[GregLocock]

Consider it as a 2dof spring mass system. m1 k1 m2 k2 ground all in series, with m1 subject to some dynamic force. The ratio m1 to m2 is important, and for good isolation should be as small as possible. Hence isolating at the base is more effective than isolating the whole platform.