I'm furring out a basement wall. I'm placing a 2-1/2" Polyiso foam board against the concrete wall and then I've got 1" thick vertical strapping every 16" OC ontop of that. That gives me a 3-1/2" thick furred out wall (which is good because I've got a subpanel to put in the wall).
So, for horizontal runs I'm planning on just running ontop of the polyiso until I get to a strap, and then I'll just burrow a quick hole through the polyiso behind the strap. Hopefully this image helps:
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So NEC 300.4(A) says that if I BORE a hole through a wood member, I need to be 1-1/4" deep, but in this case I'm not boring, I'm just slipping it behind the wood member. I didn't see any section in 300.4 that applies. Am I going to be OK in this situation?
So, for horizontal runs I'm planning on just running ontop of the polyiso until I get to a strap, and then I'll just burrow a quick hole through the polyiso behind the strap. Hopefully this image helps:
So NEC 300.4(A) says that if I BORE a hole through a wood member, I need to be 1-1/4" deep, but in this case I'm not boring, I'm just slipping it behind the wood member. I didn't see any section in 300.4 that applies. Am I going to be OK in this situation?
