From structure roof top to another

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isaacgamez said:
I have a client who has existing conduit (Emt) from his home to his detached roof. Where can i find this compliant with the code book?
thank you kindly!
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If the detached roof is considered a separate structure or building, then the sections dealing with feeding multiple buildings come into play.
Is this one branch circuit, several branches, the feeder to a subpanel?
 
There are also the conduit rules. How long is that EMT and is it supported and secured at the proper intervals?

What is a detached roof? Is there something under that roof like a patio or garage or enclosed walls?

You're not going to find this in the code book, there are separate individual rules that may have been violated. You look for rules telling you what can't be done, not what is allowed.
 
It is not detached, there is a piece of EMT connecting them:happyyes:

Depending on conditions, I would probably use RMC or IMC instead of EMT and keep any fittings out of the span, any movement at all between those structures will result in bent/broken EMT, damaged EMT fittings, or even RMC couplings can sometimes take on some damage in that situation. Another thing that happens a lot around here with EMT between two structures is snow and ice falling from a roof hits the EMT and tears it nearly completely down sometimes. Experienced guys know better and use RMC or IMC in such cases.

If it is deemed a separate structure then art 225 needs to be looked at, but there is nothing prohibiting running such a raceway between the two structures, just things like requiring a disconnecting means in the second structure or having multiple feeds to the second structure are potential problems you could run into.

ETA: I re-read the OP and I see that snow and ice is not likely much of a problem for him
 
And this is overhead, not buried, right? If so, what is the free span between them? Is that EMT over a walkway or driveway? If so, you'll have minimjum height restrictions.
 
suemarkp said:
And this is overhead, not buried, right? If so, what is the free span between them? Is that EMT over a walkway or driveway? If so, you'll have minimjum height restrictions.
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I don't think so. Most sections giving minimum clearances are for open conductors or cables, not raceways.
 
suemarkp said:
And this is overhead, not buried, right? If so, what is the free span between them? Is that EMT over a walkway or driveway? If so, you'll have minimjum height restrictions.
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Please tell where these height restrictions are located in the NEC.
 
225.16 says the point of attachment shall comply with 230.26 which references 230.24 and 230.9 (basically refers to the normal Service drop clearance requirements). I don't see this as limited to cables or open conductors only.

225.19(D)(2) seem to apply to everything too, not just cables. It references 225.18 for clearances required which is the same as typical Service drop clearance requirements.
 
suemarkp said:
225.16 says the point of attachment shall comply with 230.26 which references 230.24 and 230.9 (basically refers to the normal Service drop clearance requirements). I don't see this as limited to cables or open conductors only.

225.19(D)(2) seem to apply to everything too, not just cables. It references 225.18 for clearances required which is the same as typical Service drop clearance requirements.
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If what you are saying is true how would we ever get the conductors down to a panel or disconnect that meets maximum height requirements for the switch handles?

230.26 says "The point of attachment of the service-drop conductors to a building or other structure"

230.9(A) says "Service conductors installed as open conductors or multiconductor cable without an overall outer jacket"

230.24 says "Overhead service conductors shall not be readily accessible" If they are open conductors they are accessible which is what this section is about, put them in a raceway or under a cable jacket and this section no longer applies.
 
Because its the point of attachment to the building, not to a disconnect or box. If that attachment point needs to be 10' up in the air, there is no reason you can't come down after that to come into a disconnect.

I think what this is saying (whether it is the intent or not), is if you do an overhead drop to a building and you have cables or a raceway overhead, it needs to be high enough that it won't get struck.

Each of the final referenced rules does indicate open conductors or cables. But what sends you there is the first place does not. Not sure how to interpret in that case. Would you think it is OK to run an exposed raceway 5' above grade across where people could walk?
 
suemarkp said:
Because its the point of attachment to the building, not to a disconnect or box. If that attachment point needs to be 10' up in the air, there is no reason you can't come down after that to come into a disconnect.

I think what this is saying (whether it is the intent or not), is if you do an overhead drop to a building and you have cables or a raceway overhead, it needs to be high enough that it won't get struck.

Each of the final referenced rules does indicate open conductors or cables. But what sends you there is the first place does not. Not sure how to interpret in that case. Would you think it is OK to run an exposed raceway 5' above grade across where people could walk?
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Maybe not OK, but compliant if they could walk there. If they are intended to walk there, maybe not. I would accept GRC at 0" strapped to floors or slab, in many locations. Not all.
 
Conduit To Garage Roof

Conduit To Garage Roof

isaacgamez said:
I have a client who has existing conduit (Emt) from his home to his detached roof. Where can i find this compliant with the code book?
thank you kindly!
Click to expand...

Don't forget to look at 310.15(B)(2)(c) This is a Ambient Temp Adjustment that needs to be added to the outdoor temperature to determine the applicable ambient to be
used with tables 310.16 and 310.18.
 
suemarkp said:
Because its the point of attachment to the building, not to a disconnect or box. If that attachment point needs to be 10' up in the air, there is no reason you can't come down after that to come into a disconnect.

I think what this is saying (whether it is the intent or not), is if you do an overhead drop to a building and you have cables or a raceway overhead, it needs to be high enough that it won't get struck.

Each of the final referenced rules does indicate open conductors or cables. But what sends you there is the first place does not. Not sure how to interpret in that case. Would you think it is OK to run an exposed raceway 5' above grade across where people could walk?
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The "point of attachment" mentioned in those code articles is for the attachment point of "overhead conductors" and has nothing to do with the attachment of any raceway. Op has a raceway that happens to have a little elevation to it, but doesn't have any "overhead conductors".
 
So what does overhead mean? It isn't direct buried, and you could argue that something at shoulder level isn't overhead. A raceway at 7' over the ground isn't overhead conductors?

I see no definition of overhead conductors in the NEC except on Services.

225.19 is not restricted to overhead conductors. Subparts (D) and (2) say "final span" and do not say "overhead". This refers you to 225.18 for height restrictions. You'd have to do 225.18 anyway if you were running overhead open cables/conductors. Why refer you back 20 225.18 if it didn't apply in some different way?
 
suemarkp said:
So what does overhead mean? It isn't direct buried, and you could argue that something at shoulder level isn't overhead. A raceway at 7' over the ground isn't overhead conductors?

I see no definition of overhead conductors in the NEC except on Services.

225.19 is not restricted to overhead conductors. Subparts (D) and (2) say "final span" and do not say "overhead". This refers you to 225.18 for height restrictions. You'd have to do 225.18 anyway if you were running overhead open cables/conductors. Why refer you back 20 225.18 if it didn't apply in some different way?
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Just because you'd want to know the allowable clearance of a quadreplex or similar.
 
suemarkp said:
So what does overhead mean? It isn't direct buried, and you could argue that something at shoulder level isn't overhead.
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I agree.

suemarkp said:
A raceway at 7' over the ground isn't overhead conductors?
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No it is an overhead "raceway" the conductors are inside. The sections in question are referring to "open conductors", and not conductors contained in a raceway or cable. wouldn't all conductors in raceways run on ceilings be overhead conductors otherwise, then we wouldn't be allowed to run raceways on ceilings (or at least not be able to pull conductors through them) if the ceiling were not high enough for clearance requirements.

suemarkp said:
I see no definition of overhead conductors in the NEC except on Services.
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I don't even see a definition there.

suemarkp said:
225.19 is not restricted to overhead conductors. Subparts (D) and (2) say "final span" and do not say "overhead". This refers you to 225.18 for height restrictions. You'd have to do 225.18 anyway if you were running overhead open cables/conductors. Why refer you back 20 225.18 if it didn't apply in some different way?
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Subpart A does mention open conductors, I do notice the other parts do not mention open conductors - I kind of get the feeling the intent is that it applies to open conductors, it probably needs some changes to better indicate this. But at same time title of the section is sort of indicating this also "Clearances from Buildings for Conductors of Not over 600 Volts, Nominal." Title does not say "clearances.... for raceways....."
 
kwired said:
No it is an overhead "raceway" the conductors are inside. The sections in question are referring to "open conductors", and not conductors contained in a raceway or cable. wouldn't all conductors in raceways run on ceilings be overhead conductors otherwise, then we wouldn't be allowed to run raceways on ceilings (or at least not be able to pull conductors through them) if the ceiling were not high enough for clearance requirements.
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No. Article 225 deals with circuits TO a detached structure. These rules are only appling at the connection TO the structure, not once you're distributing circuits around inside it. So run at whatever height you want once you're past the structure disconnect.
 
suemarkp said:
No. Article 225 deals with circuits TO a detached structure. These rules are only appling at the connection TO the structure, not once you're distributing circuits around inside it. So run at whatever height you want once you're past the structure disconnect.
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That is correct, but the clearances in discussion only apply to open conductors, not conductors inside of a raceway. The OP does not have any exposed conductors between the buildings, just a raceway that spans between two buildings that are apparently close enough to one another there is no raceway support issues.
 
And that's where I disagree (open conductor -vs- any high up feed to a building), and could certianly be wrong. I'm not an electrician, and can only read the code and guess what they meant. Someone probably taught you that this is what was meant, and that's required in many sectrions of the book. They just don't always spell things out clearly, as we've seen from numerous proposals to fix obviously poor language time and time again.
 
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