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Discussion Starter · #1 · (Edited)
I'm looking for suggestions on how to wire a cavity wall system.
The 12" wide wall cross section is 2" of lightweight concrete exterior face, 2" polyiso bonded to the back side, 4" on cast in place regular concrete, then a repeat of the polyiso and finally 2" lightweight concrete on the opposite face.

Cross section of vertical standing wall:




Looking down into wall cavity:



Electric boxes are cast into the lightweight concrete panels and accessible from the backside in the cavity before the cast in place concrete is poured down the center. The shown expanded steel wall couplers are on 12" centers.

How would one wire in this situation?

Thanks for your suggestions.:thumbup:
 

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Can you pipe out the top of the box into the ceiling?
 

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Discussion Starter · #3 ·
Can you pipe out the top of the box into the ceiling?
Yes, conduit can be in the center third of cast in place concrete thickness. It would be nice to not use conduit to maybe slot the wire into the insulation but for the long haul, conduit may be necessary.

Finding a box that would have conduit knock outs centered 6" from the wall face seems a challenge.

The ceiling will be a 6" thick cast in place elevated concrete slab.
 

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The stuff I've seen had wiring chases cast into the concrete. We used rigid, but I'm guessing your situation is different.
 

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Discussion Starter · #5 ·
Seems I could cast a chase into the wall panel back side which would then be covered by the rigid insulation board. What size would the chase need to be and what kind of wire is permitted?

Then I could use a thin box. The chase would need to be deep enough to get into the box yet not compromise the panel strength.

What about attaching wire to the back side of the insulation board (center of the wall side) and having the cast in place concrete pour up against it?
 

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I just don't know. Ours were engineered for the wiring chases and I really haven't worked those systems for many years. How about concrete tight flex looped in before the pour is made?
 

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Seems I could cast a chase into the wall panel back side which would then be covered by the rigid insulation board. What size would the chase need to be and what kind of wire is permitted?

Then I could use a thin box. The chase would need to be deep enough to get into the box yet not compromise the panel strength.

What about attaching wire to the back side of the insulation board (center of the wall side) and having the cast in place concrete pour up against it?

What kind of wire are you thinking?
 

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Sounds like a fine applincation for ENT.
 
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