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Advice on running conduit through a standing seam metal roof

corbin

corbin

New Member
Joined
Apr 22, 2024
Messages
8
Location
Truckee, CA, USA
Hi! I'm installing REC410 panels on the standing seam metal roof of my shop. It has no exposed fasteners. Does anyone have any good recommendations for installing conduit through the roof, and not having it leak?

I'm debating a hole through the roof versus just running the conduit off the eave edge and into the building from there.
 
Are there no plumbing or air vents through the roof?

Google shows lots of boots, flashing and jacks to allow conduit through the metal roof.

Over the edge is a bad look to me.
 
I learned to never penitrate a roof membrane or metal roof in your case. Just one more spot to possibly get a leak that would need a later repair.
I usually transitioned off roofs with an LB conduit body.
 
time2roll said:
Are there no plumbing or air vents through the roof?

Google shows lots of boots, flashing and jacks to allow conduit through the metal roof.

Over the edge is a bad look to me.
Click to expand...
Nope, nothing penetrates the roof. It's an 1800sf detached garage/workshop; no plumbing, and no venting required.

I know it looks bad...but I am leaning towards doing it over the edge with LB's; it's on the side of the building that won't be as visible.

Thanks everyone for the replies, and thanks kampto for the boot recommendation. I also found some slick "Zilla XL Adapters" that look nice, but I think I'm going to skip the hole for this project and go over the edge.
 
How about near the ridge, put flashing over it folded down both sides?
 
Hedges said:
How about near the ridge, put flashing over it folded down both sides?
Click to expand...

I guess I'm just not sure how to flash it properly; I don't have metal roofing skills. This would definitely look cleaner, but I don't think I'm too concerned about the looks. I appreciate the ideas though!
 
Lots of ways to do it. If done near the peak then it never has much water run over it.

I'm going to guess it's a nice looking building if you spent the cashola on a concealed fastener roof.

You just use a standard plumbing boot but urethane sealant and an LB with some kick out flashing works good too.

It's akin to the body seam sealer they use on vehicles and lasts forever on roofs.
 
I just went through the same thing and just wrapped around the roof. If I ever change my mind, it's easy to remove.
1714587880062.png
 
Actually it's ok to use this kind of bend, as long you are not going over 360 degrees between the pull points.
It's called a "Shepard hook". I saw it a few times, and used it by myself also.
 
Everything I found was no more than 3 90's in a pull. I have a little less than 3. The final bend to get on the roof is about 67°. I have an LB at each end.

This shows a little better. (And also my first ever conduit bend so I didn't think I did too bad.)
1714590526842.jpeg
 
timselectric said:
A continuous conduit bend of more than 90° is a big no no.
While it looks neat, it would not pass an inspection.
Click to expand...
My AHJ installed this for me, so I know it meets their requirements. What's wrong with a more-than-90-degree bend (from a technical POV, not 'cuz code sez so')?

IMG_6056.jpeg
 
TechRider said:
Everything I found was no more than 3 90's in a pull.
Click to expand...
It's actually a limit of 360° of total bends, between pulling points.
And no single continuous bends of more than 90°.
But most people follow the 3 90's rule of thumb. (Myself included)
TechRider said:
This shows a little better. (And also my first ever conduit bend so I didn't think I did too bad.)
Click to expand...
It is straight and well performed.
 
wpns said:
My AHJ installed this for me, so I know it meets their requirements.
Click to expand...
That looks like flexible conduit. If it is, then it's fine. Because it's assumed that the conductors are placed in the conduit before it's bent.
wpns said:
What's wrong with a more-than-90-degree bend
Click to expand...
Too much friction and tension placed on the conductors, when being pulled through the conduit.
 
I'm going to concede this one to interpretation. (As many things in the NEC are)
The code has always been "not more than the equivalent of 4 quarter bends (90°), in a single run. (Which is a total of 360°)
But, after a bit of research, just now.
Some people don't believe that "quarter bends" (90°) is the maximum allowed single bend radius. (I always have)
But since it's open for interpretation. It's up to your local AHJ (and their interpretation), if it will pass.
It has failed inspections in my area. But could be acceptable in yours.
I can only say that it's never been something that I would do.
 
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