Low Voltage conduit crossing expansion joints

[mickmast]

Hello

Im working on a project where we have pvc conduit that be be run through the concrete decks. The multi-story structure is being fabricated with multiple expansion joints and we're being told that our conduits cannot cross the expansion joints, thus putting some areas out of distance because the comm rooms are on the other side of the EJ. Does any one know of an approved means or products to put conduit through the EJ, so devices on the other side are with the allowable distances for ethernet. We've looked at some expansion fittings but they only move horizontally but no vertical expansion?

Thanks,

Mick

 

[gadfly56]

Hello

Im working on a project where we have pvc conduit that be be run through the concrete decks. The multi-story structure is being fabricated with multiple expansion joints and we're being told that our conduits cannot cross the expansion joints, thus putting some areas out of distance because the comm rooms are on the other side of the EJ. Does any one know of an approved means or products to put conduit through the EJ, so devices on the other side are with the allowable distances for ethernet. We've looked at some expansion fittings but they only move horizontally but no vertical expansion?

Thanks,

Mick

If you use something like a loop of Greenfield across the joint attached to the PVC on either side, that will give you both horizontal and vertical deflection. We had to do something like this for LaGuardia Terminal B. It was some insane amount, like 13" vertical and 5" horizontal, or some such. You'll need a box or pit to accommodate the loop.

 

[mickmast]

Thank you for this, we don't have nearly as much deflection as that. You would happen to have a drawing detail for this?

 

[gadfly56]

Thank you for this, we don't have nearly as much deflection as that. You would happen to have a drawing detail for this?

Sorry, no. The detail was eventually supplied by the contractor. I was with an MEP firm at the time.

 

[mickmast]

OK, Thanks