We've all fished between strapping…but

[CobElectric]

So everyone fishes romex between strapping (in a ceiling) to feed lights or to an opposite wall. So Im wireing a new second floor addition upgraded from an existing accessible attic space. There is no sub floor on the second floor addition except below the newly installed interior and exterior walls, thus the existing rafters are accessible. However these rafters are very old, green material and have some minor cracking as it is. I could glue and screw in plywood on the rafters to increase their strength to bore holes. But as the rafters have strapping beneath them for the existing first floor ceilings, I had a thought. What if I fished under those previously mentioned rafters (despite them being accessible for drilling) and just popped up in the walls without boring holes anywhere but in the floor plates of the interior walls. It would be quick and reduce penetrations. I can’t decide definitively

 

[Seven-Delta-FortyOne]

If the rafters are more than about a year old, they are no longer “green”.

We don’t do this “strapping” thing Out West, but from what I hear of it, I would have zero issue with fishing romex through it.

 

[LarryFine]

Welcome to the forum.

By all means run the cables between the strapping.

We don't build with ceiling strapping here either.

 

[tortuga]

Can you post a photo?

 

[LarryFine]

 

[LarryFine]

Except the OP has the ceilings in place, so the cables would be slid into place and not be stapled.

To me it's the same as fishing cables between wall furring strips, perfectly acceptable.

 

[tortuga]

I agree its better than drilling but that looks like the cables will by laying on the ceiling.
I'd use a nail tube in that case.
Since there is a ceiling in place I'd probably sprayfoam to hold the tubes in place.

 

[CobElectric]

If the rafters are more than about a year old, they are no longer “green”.

We don’t do this “strapping” thing Out West, but from what I hear of it, I would have zero issue with fishing romex through it.

So “green material” is sometimes a way of referring to old “true dimensional lumber”

 

[CobElectric]

Welcome to the forum.

By all means run the cables between the strapping.

We don't build with ceiling strapping here either.

Thank you sir

 

[CobElectric]

completely agree with both you and @tortuga . The Nec handbook in 300.4 only requires that you maintain the 1 1/4 distance from furring strips and in this case spray foam would help with that. I guess my only concern is that the Inspector will say that because the rafters are exposed I should be drilling them. This picture doesn’t show them very well but these rafters are beginning to crack all over the place. The wires in the photo were fished previously under the old attic floor

 

[LarryFine]

If you use spray foam, make it minimally expanding. Or use little wedges of foam rubber.

 

[CobElectric]

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I always thought this was illegal In Massachusetts on a new build but I cant find anything in the NEC saying I cant either