Gray electical PVC used for waste line plumbing

[montana]

I 'know' it's wrong, but can't find an obvious answer why not. 1983 house with mixture of ABS and white PVC, and quite a bit of gray schedule 40 PVC electrical condiut for waste line plumbing. Stamp on the gray PVC says [1-1/2" CARLON PVC CONDUIT, "PV DUIT 40 PLUS", NEMA TC2]. This is obviously electrical PVC conduit. Since there is no ASTM stamping, it is obviously not intended for plumbing. My stupid question of the day is why is this Schedule 40 PVC not suitable for waste line plumbing? Is there some sort of chemical reaction? Is it because the solvents for white plumbing PVC don't bond with electrical PVC?

[Brian G]

I'm sure there are technical reasons why it's wrong, but it's not because it won't glue-up to the white stuff.

The truth is that electrical stuff is way tougher than the white stuff. Back when I didn't know any better I used electrical PVC for a water supply line to my old house trailer. Years later we had to run a second line in the same place for a house, and the trencher did little more than scrape the outside of the electrical stuff when we got too close. I would be happy to have sch. 40 electrical PVC for waste lines.

If it were my job I would tell them it was technically wrong, but should be no problem now or later. Others may be inclined to disagree.

Brian G.

One of Those No-Problem Problems [8]

[montana]

The plumbing is what I call a real mish-mash of materials. I see lots of indications of prior leaks on the plastic moisture barrier, but from what I see most of that appears to be from supply lines (some sloppy joining of CPVC and galvanized supply lines).

Living in a rural area like this, I tend to not jump up and down on every little thing that doesn't technically meet code, especially on older stuff. And its not like they used it for water supply lines.

I will note that it is technically incorrect (to cover my tail so when the client sells it in 3-5 years), and defer to a plumber that he needs to call out for a different reason anyway.

If anyone has a different opinion, please yell.

[Bill Kibbel]

I don't know know of any reason why it wouldn't work for DWV. I see it occasionally used without any issue.

The big difference is the color coding. This is intended to reduce the possibility of mistaking installed electrical conduit for plumbing. I know of one incident that the installer of a water softener tapped into gray conduit for the backwash discharge hose.

[Kyle Kubs]

Originally posted by inspecthistoric

I don't know know of any reason why it wouldn't work for DWV. I see it occasionally used without any issue.

The big difference is the color coding. This is intended to reduce the possibility of mistaking installed electrical conduit for plumbing. I know of one incident that the installer of a water softener tapped into gray conduit for the backwash discharge hose.

Well that would be a good reason...

- Technically they're both PVC so it will work but my fall back would be that by code the gray pipe is not listed for that purpose.

[Jim Katen]

Originally posted by montana

. . . My stupid question of the day is why is this Schedule 40 PVC not suitable for waste line plumbing? Is there some sort of chemical reaction? Is it because the solvents for white plumbing PVC don't bond with electrical PVC?

It's not suitable because no one paid to have it tested for that purpose.

Will it carry wastewater and not leak? Probably.

The real problem with it, from an inspector's point of view, is that it's a bright glaring neon sign that says, "This house was plumbed by someone who had no idea what he was doing." It means that the plumbing system, and possibly other systems in the house, is going to be a cobbled together improvisational comedy routine.

- Jim Katen, Oregon

[Chad Fabry]

The real problem with it, from an inspector's point of view, is that it's a bright glaring neon sign that says, "This house was plumbed by someone who had no idea what he was doing." It means that the plumbing system, and possibly other systems in the house, is going to be a cobbled together improvisational comedy routine.

I used 4 inch schedule 80 steel for dryer duct in my rental property. It's inappropriate but I'd judge the level of craftsmanship before I judged the material.

When I see bar codes on product... that's what makes me nervous.

[Jim Katen]

Originally posted by Chad Fabry

The real problem with it, from an inspector's point of view, is that it's a bright glaring neon sign that says, "This house was plumbed by someone who had no idea what he was doing." It means that the plumbing system, and possibly other systems in the house, is going to be a cobbled together improvisational comedy routine.

I used 4 inch schedule 80 steel for dryer duct in my rental property. It's inappropriate

Nope. It's peculiar, but it's not inappropriate. The only requirements for dryer vent material are that it be metal (at least .016" thick), smooth-walled and rigid. Your steel pipe meets these criteria.

but I'd judge the level of craftsmanship before I judged the material.

I judge both.

When I see bar codes on product... that's what makes me nervous.

Sure.

So why did you use schedule 80 steel? Were you out of stainless?

- Jim Katen, Oregon