# PVC under driveway: Sch 40 or 80?



## Cow (Jan 16, 2008)

It doesn't exist.


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## gpop (May 14, 2018)

might have something to do with the depth


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## 99cents (Aug 20, 2012)

Might be a utility requirement.


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## Southeast Power (Jan 18, 2009)

I just had a job with sch 80 specified under a commercial driveway. 
3” sch 80 is $20 more per 10’. Almost $60 per stick


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## mikewillnot (Apr 2, 2013)

99cents said:


> Might be a utility requirement.


Not in this case. I believe it's a mistake. OR heresay. Or made up. Or fake news.


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## varmit (Apr 19, 2009)

How deep was your PVC buried? if less than 18 inches, Sch. 80 would be required. See NEC 300.5


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## mikewillnot (Apr 2, 2013)

In this case it was HDPE, directional boring, and at the driveway it was probably 36"
The inspector referenced the requirement for PVC, and said it might or would apply here also.


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## Dennis Alwon (May 9, 2009)

It is really an inspectors call as to whether the install is subject to damage



> (4) Enclosure or Raceway Damage. Where the enclosure or
> raceway is subject to physical damage, the conductors shall be
> installed in electrical metallic tubing, rigid metal conduit, intermediate
> metal conduit, RTRC-XW, Schedule 80 PVC conduit,
> or equivalent.


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## 99cents (Aug 20, 2012)

The directional drilling guys usually pull in HDPE. Is that allowed?


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## Aaron Owens (Nov 17, 2020)

mikewillnot said:


> In this case, it was HDPE, directional boring, and at the driveway, it was probably 36"
> The inspector referenced the requirement for PVC, and said it might or would apply here also.


At the end of the day the inspector, being the AHJ, has the final say unless you have a board or committee you can submit a review. However, based on the NEC this is what I find:

HDPE per NEC 353.6 says that the conduit is to be listed for the installation. 

353.10(4) says that it can be direct burial in earth or concrete. The note refers to table 300.5

353.12(1) says it cannot be used "Where Exposed"

I would say that HDPE would fall under column 3 in table 300.5 since it is a Non-Metalic Raceway, but is must be "Listed" for direct burial. Under a driveway or parking lot, it has to be 24"

300.5(D)(4) "Enclosure or Raceway Damage - Where the enclosure or raceway is subject to physical damage, the conductors shall be installed in.....Schedule 80 PVC..."

My understanding would be this: HDPE would be allowed to be used underground as long as the type you're using is listed for that use. It would have to be at least 24" for under the driveway, however, you would have to transition to PVC before emerging from the ground. Whether the conductors are subject to damage is subjective, some people would say that everywhere is subject to damage.....

Ultimately you have to determine whether it is in your best interest to argue the inspector's requirements. Does the jurisdiction that the inspector works for have an adopted code that overrides the NEC? If not, Do you have a board or committee that you can present this to? Or would it be better to just comply???


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## readydave8 (Sep 20, 2009)

Aaron Owens said:


> At the end of the day the inspector, being the AHJ, has the final say


Don't most inspectors have a boss? Or similar


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## Aaron Owens (Nov 17, 2020)

readydave8 said:


> Don't most inspectors have a boss? Or similar


Obviously not every municipality, county or state has the same structure, but I would dare say that each jurisdiction has an ordinance that has a way to handle grievances and to discuss code application. The inspector has a boss, whether a director or city planer for example, but the inspector is usually given the authority over his jurisdiction and going to the boss is generally not the appropriate way to handle the dispute. Generally there is a way to have a public hearing to review the application of the code by the inspector. It usually has enough bureaucratic red tape to make it difficult for a quick resolution.
That’s the way it is in the states I work in. I can’t say for certain how things work in all places.
Some inspectors are reasonable to discuss code, especially if you’re knowledgeable. Others are dead set on their knowledge and there’s no discussion.
FYI - I was an electrical inspector in my area for 3 years. I had people try to go over my head to my boss. The local ordinance required a public hearing before the electrical board to settle those issues.


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## mikewillnot (Apr 2, 2013)

OP


Aaron Owens said:


> I would say that HDPE would fall under column 3 in table 300.5 since it is a Non-Metalic Raceway, but is must be "Listed" for direct burial. Under a driveway or parking lot, it has to be 24"
> 300.5(D)(4) "Enclosure or Raceway Damage - Where the enclosure or raceway is subject to physical damage, the conductors shall be installed in.....Schedule 80 PVC..."
> My understanding would be this: HDPE would be allowed to be used underground as long as the type you're using is listed for that use.


I have done a number of such jobs last year or two, different jurisdictions. In every case, I pull in cable rated for direct burial. I've not yet had any inspector raise an issue. Just this one who mentioned something about 80 under driveways. Even he didn't seem too sure of himself.


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## MartyB913 (Dec 5, 2021)

I suggest installing fireproof PVC, AND I also need to be located a few meters from the existing object


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## Majewski (Jan 8, 2016)

presumably is there local amendments?


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## SWDweller (Dec 9, 2020)

Your description is vague. What/which conductors? If they belong to the POCO then you must follow those rules/regs. There are lots of driveways, some are for commercial weight trucks.
Some are strickly residential. Then there is the freeze thaw cycle and the depth you dug the trench. Last what is the quality of the bottom of the trench? If no rocks that is one thing if the ground is rocky then sleeving would be part of the program for me. 

I know of no code that requires sched 80 under a ribbon of concrete. 
Where I live the POCO uses DB 120 for sleeving, 4 feet deep trenches. 


Sleeving under a concrete slab is always a good idea when looking into the future. 







I


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## Majewski (Jan 8, 2016)

Sooooooo vague


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## R777V (May 16, 2016)

Is it worth wasting your time to argue it before some city official prolonging a job? For the cost of some PVC I wouldn’t bother you’d eat that up in wasted time, and then end up losing your argument and doing it anyways!


Sent from my iPhone using Tapatalk


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## mikewillnot (Apr 2, 2013)

[OP:] To repeat:


mikewillnot said:


> In this case it was HDPE, directional boring, and at the driveway it was probably 36"
> The inspector referenced the requirement for PVC, and said it might or would apply here also.


There is/was no trench. It was directionally drilled. 
It was a residential driveway, recently repaved. That is the main reason we drilled.
Depth is not relevant here, as by the time the drill reached the driveway the depth was around 36".
The conduit the driller pulled in was probably schedule 80, I don't remember. HDPE comes in version listed for electrical use, and I believe it's schedule 80. I've used this sub a number of times, and ever since the first job, they use listed materials.
The conductors we pull in are, in virtually all cases, rated for direct burial.
At each end of the HDPE we transition, before breaking the surface: to PVC at the house, to RMC at the pole. 

My question was about the existence of an NEC rule requiring Schedule 80 under a residential driveway. Dennis Alwon came up with the closest answer, I think.


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## Quickservice (Apr 23, 2020)

mikewillnot said:


> Not in this case. I believe it's a mistake. OR heresay. Or made up. Or *fake news*.


We are the land of fake news!


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