2005 NEC 352.10/300.5

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VIC1958

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I had an electrician install a feeder from the meter can to the electrical panel in a new residential house. The top of the PVC piping used was located approx. 1"-3" below the crushed gravel that was being used as a sub base for the garage concrete floor. It is my opinion that this conduit would have to be a minimum of 18" below the top of the gravel. The electrician is claiming that the conduit is UNDER the building, therefore it would be 0". Is there a definition of under building? I believe that if cars are driving and being parked on top of the conduit, it needs to be 18". Thoughts?
 
I agree with the electrician. What do you mean "Is there a definition of under a building"? I can walk up to pretty much any building and tell the parts that are and are not under it. No need for eighteen inches of cover. Table 300.5 says zero is acceptable in every column.
 
ActionDave said:
I agree with the electrician. What do you mean "Is there a definition of under a building"? I can walk up to pretty much any building and tell the parts that are and are not under it. No need for eighteen inches of cover. Table 300.5 says zero is acceptable in every column.
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X2

Jap>
 
ActionDave said:
I agree with the electrician. What do you mean "Is there a definition of under a building"? I can walk up to pretty much any building and tell the parts that are and are not under it. No need for eighteen inches of cover. Table 300.5 says zero is acceptable in every column.
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The electrician skates only because he is stretching the rule.

That area is really subject to traffic, which is a major part of 300.5.

Yeah, no one is gonna park a 30 ton tank in there , but...

Think of a major commercial garage. Can I use your idea of zero inches?
 
Not only is it going to be under the building, its going to be under more than likely 4 inches of concrete.

JAP>
 
If it's within the concrete there is no minimum depth so why would there be one if were in the stone?
 
I ain’t gonna argue this, but I still say it is BS.

Pipe has to be 18” below my driveway, but is now magically safe when I pull into my garage?:huh:

It is a resi app and nothing will ever come out of it. I see the point, but..

Try this in a major commercial garage and come back and tell me that plans review did not die laughing...
 
jumper said:
I ain’t gonna argue this, but I still say it is BS.

Pipe has to be 18” below my driveway, but is now magically safe when I pull into my garage?:huh:

It is a resi app and nothing will ever come out of it. I see the point, but..

Try this in a major commercial garage and come back and tell me that plans review did not die laughing...
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Come on, lets argue a little bit at least. :)

A heavy rain on your driveway may cause a heavy vehicle to sink down to a considerable depth.

If your commercial garage with a concrete floor ever has that issue, or, your residential garage with 4" of concrete floor for that matter, we'd be the ones laughing at the designers instead of them laughing at us.

JAP>
 
infinity said:
If it's within the concrete there is no minimum depth so why would there be one if were in the stone?
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Because the 2" of concrete above the conduit exploding looks much cooler when you drill into the conductors with your 6" concrete bit thank does simple loose gravel. :p


JAP>
 
Well, don’t know what the AHJ in states is doing about this one but... Jamaica right now isn’t taking the attitude that since so many decide not to do the concrete work for a long time, the trench and such should be done to at least 18 inches under the gravel, just in case cement work is not done. They have said that at two different houses in my neighborhood.
Probably the only section of code I have actually seen the inspectors using... other than their insistence upon grease traps from the 1950’s when the British no longer require them..lol...
 
ActionDave said:
I agree with the electrician. What do you mean "Is there a definition of under a building"? I can walk up to pretty much any building and tell the parts that are and are not under it. No need for eighteen inches of cover. Table 300.5 says zero is acceptable in every column.
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My intrpertation of under building would be under the the footing and foundation walls.
 
Still does not answer his question..lol... if the concrete does not get poured over the driveway area then it should have been 18 inches below surface... if concrete gets poured and it is at least two inches below surface of concrete it is legal...
in Jamaica we have to use the 18 inch rule because so many plan to put concrete in place but do not for cost reasons... in US I think most buildings are built so differently that the contractor may be assured that concrete work is done before consumer moves in.. so could set up as shown in original question and be legal.. because concrete would be poured before inspections done.

of course, I could be wrong...lol.
 
Adamjamma said:
Still does not answer his question..lol... if the concrete does not get poured over the driveway area then it should have been 18 inches below surface... if concrete gets poured and it is at least two inches below surface of concrete it is legal...
in Jamaica we have to use the 18 inch rule because so many plan to put concrete in place but do not for cost reasons... in US I think most buildings are built so differently that the contractor may be assured that concrete work is done before consumer moves in.. so could set up as shown in original question and be legal.. because concrete would be poured before inspections done.

of course, I could be wrong...lol.
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It the garage floor, not the driveway. Driveways are clearly 18”.
 
jumper said:
hmmm..personally I agree with you.

I would say that the garage floor is really part of the driveway in a sense.
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And if you hit the accelerator instead of the brake and drove through the wall into the kitchen, by default the kitchen is now part of the driveway?:angel:
 
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