Sand Bags

[Billdings314]

Hey Folks,

Question-- I have a cable tray support that will be atop a roof. (3' bent width, 4' tall, w/ (2) 18"x18"x3" thick square feet, the feet are not weighted)
The cable tray, support, and feet wont have enough weight to resist overturning from wind.

I can't fasten this support to the roof because of the nature of the project & and the nature of the insides of the building that this support will sit atop of.
Therefore I would like to sandbag the base of the support. It doesn't need much weight so I was thinking (2) 25lb sandbags per foot.

my questions are: how do I call out a sand bag on my structural drawings?
Feel free to also give me any other advice to ensure the contractor can knock this out w/o a sea of RFI's!

name of the support is a PPH-D cable tray support
Thank yall

 

[JAE]

I'm not sure I'd use sand bags - fearing that the bags might tear, deteriorate, or otherwise allow sand to escape - with nothing left to really hold down the tray.

I've typically seen concrete blocks, or cast concrete shapes used as dead weight.
Here's some photos:

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[JAE]

Also systems like this:

https://www.phpsd.com/rooftop-support-projects/high-wind-resistant-pipe-supports

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[MotorCity]

Agree w/ JAE, use CMU blocks or other proprietary devices. We have used Cush-A-Blocks w/ success, Google it. Its basically an H-shaped frame for supporting utilities (similar to what JAE linked to, which we have also used).

 

[JLNJ]

You might talk to your client's roofing consultant to find out what they like to see. You don't want to inadvertently void your client's roof warranty.