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?

 

[canwesteng]

Your best bet would be isolators such as springs below the unit, from an ease of install perspective. Is the floor shaking now?

 

[jhnblgr]

Its best to mitigate vibration at the source.

 

[Harbringer80]

As mentioned by canwesteng a spring isolator curb is the typical solution for this.

 

[GTrinh97]

Your best bet would be isolators such as springs below the unit, from an ease of install perspective. Is the floor shaking now?

Yes — the unit is currently causing noticeable vibration.

Since this is an existing installation, lifting the unit to install isolation directly beneath it would be costly and complicated. I’m exploring whether it would be more practical to shore the structure temporarily and install isolation pads between structural framing elements instead like at column cap or somethings like that

 

[GTrinh97]

As mentioned by canwesteng a spring isolator curb is the typical solution for this.

Since this is an existing installation, lifting the unit to install isolation directly beneath it would be costly and complicated. I’m exploring whether it would be more practical to shore the structure temporarily and install isolation pads between structural framing elements instead like at column cap or somethings like that

 

[Harbringer80]

Since this is an existing installation, lifting the unit to install isolation directly beneath it would be costly and complicated. I’m exploring whether it would be more practical to shore the structure temporarily and install isolation pads between structural framing elements instead like at column cap or somethings like that

Tough to say if the improvement of pads would result in enough of a reduction in vibration.

I'd expect that the pads would be significantly less effective than an iso-curb.

 

[canwesteng]

So instead of lifting the unit, you are going to jack up the entire building? I don't see a world where this is cheaper. It also may not stop whatever is about the isolators from shaking, depending on what is being excited.

 

[271828]

Contact Kinetics Noise Control and see if they have any ideas.

Spring isolators at the unit will probably be the answer.