Sch 40 vs 80

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nizak

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Seems that more and more I am encountering inspectors who want to see Sch 80 PVC installed in places that never were an issue before.

Seems a waste of time when the MTA's and the LB/LL/ and LR conduit bodies are the equivalent of Sch 40.
 
GoldDigger said:
Hmm. All this time I thought the fittings were all Schedule 80 equivalent.
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Although I think I've heard hearsay that they are, but undoubtably the thickness of the wall of fittings as OP describes I would have to agree with him. But I guess I should look at an ordering book and see if there really are sch.80 fittings.
 
Well, Schedule 80 and Schedule 40 fittings are both compatible in size with either wall thickness pipe. For plumbing uses 80 is required for some industrial, agricultural, and distribution uses where pressures are higher.
And for plumbing fittings most 40 fittings are white and most 80 fittings are gray. The possible significance of color for electrical fittings is unclear to me. :)

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GoldDigger said:
The possible significance of color for electrical fittings is unclear to me. :)

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maybe so when you dig a white is "oh man, i broke that water pipe", but gray is, "oh #@!#@$!, just broke electrical pipe, now this is a pita, dont get too close, dont touch it".

gray typically has UV blockers in it. PVC in just about every color is available to be made, selection of cots colors maybe limited, and white gray PVC is most common in use, black ABS is also common.

rolls of PEX seems like where the industry might be moving to.
 
Speaking from the pool plumbing world, Sch. 40 PVC is white and Sch.80 is gray. The difference is the inside diameter. Sch. 80 is thicker and is sometimes called out for on some commercial projects. Right now we have called out for on a residential build for a fire hydrant hook up utilizing the pool water as a way to fight a possible fire. The engineer is spec'ing Sch. 80.

Yes, when identifying buried pipe, white is usually water and gray is usually conduit. But the gray may be Sch.80 water pipe. We ran across this last fall on a reno job. The buried gray pipe turned out to be part of the original water piping for the pool.
 
I have seen many Sch 80 installs with broken fittings.

I have seen sch 40 that goes straight down into the ground that survives a long time with no damage - and if there is any often involves the fittings.

If you want it to last nearly forever, bury PVC but turn up to emerge from grade with a RMC/IMC elbow and continue up with RMC/IMC.:happyyes:
 
Fulthrotl said:
there are, for plumbing. not for electrical.
all electrical are sch. 40.
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The common outside diameter to both schedules is what makes it possible to use the same inventory of fittings to fit both. Factory elbows have separate product lines for each schedule.

It does beg the question of whether using that same inventory of fittings for schedule 80 is enough protection from "physical damage". I would like to see these fittings carry a dual rating, so there would be a way to convince a skeptical inspector that the installation complies. You wouldn't be allowed to use schedule 80 plumbing fittings with schedule 80 electrical because it isn't listed for the application, but that is the only way you can actually find schedule 80 fittings.

One fitting in particular, where there should be a version for Schedule 80, is the bell end. A fitting that provides a rounded opening for wire to exit. In schedule 40, the interior curvature lines up with the conduit ID, and the fitting works as designed. In schedule 80, half of the conduit wall is still exposed with its sharp inner edge. The end bell does nothing for you, and you have to bevel the interior edge with a unibit.
 
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