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PVC vent pipes


Neal Lewis
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The vent stack goes up through the roof, and the pic isn't upside down. PVC is used regularly here for vents with no UV protection.

Yeah, I would say it's construction adhesive, come to think of it.

And what prevents plasticizer migration?

And not it is not accepted by the manufacturers.

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The vent stack goes up through the roof, and the pic isn't upside down.

Neal, that 'T' looks upside down. Shouldn't it drain downwards instead of upwards?

Marc

That's the correct configuration for a vent fitting. Vent piping is supposed to drain back toward the fixture. The fitings have a 1/4" per foot pitch built into them. If you were to install the fitting "right side up," the pipes that you attached to it would pitch the wrong way.

- Jim Katen, Oregon

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Does the PVC pipe penetrate the roofline? If so is it UV protected, and does it have mastic on it?

NJ ain't sunny California.

So the laws of chemistry and physics don't apply in New Jersey? Silly me, thinking that Industry standards applied to all 50 states. As long as the sun shines on New Jersey and mastics contain bitumen and solvents the reactions will be the same, the only variable is time.

I have seen mastic applied to PVC vents at roof penetrations. The PVC has become gelatinous then two inches away where exposed to UV the PVC is brittle.

If we do not learn from our mistakes we are doomed to repeat them.

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What industry standard are you referring to? Is there something you can show us that requires PVC vents have field-applied "UV protection" in our jurisdictions? Are you familiar with the required formulations for pipe grade PVC?

When would it ever be acceptable to apply mastics containing bitumen to a plumbing vent penetration?

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Hi,

Rocon, your first response made it sound like you wanted mastic applied and wanted to see some UV protection. After your second post, it sounds like you disapprove of applying mastic to PVC but also want to see the PVC protected from UV - have I got that correct?

If so, I agree that using a petroleum-based mastic on PVC is probably going to dink it up but I'm not entirely convinced that UV is going to damage it to the extent where it's "brittle" as you've stated. I inspected a 10-year old PVC roof the other day that's not coated with any inhibitors of any kind and it seems to be able to handle the UV just fine.

What standard are you using?

ONE TEAM - ONE FIGHT!!!

Mike

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What industry standard are you referring to? Is there something you can show us that requires PVC vents have field-applied "UV protection" in our jurisdictions? Are you familiar with the required formulations for pipe grade PVC?

When would it ever be acceptable to apply mastics containing bitumen to a plumbing vent penetration?

When the neoprene flashing boot fails and a seller is too cheap to replace it. I've seen pretty much every kind of stick-um stuff in the universe used to seal cracks in boots.

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Bill and Mike

FYI

California has been on the Uniform Plumbing Code for decades and printed with the code are the installation standards. Some of these years ago had to be adopted separately by the AHJ but under the current code the protection required all approved plastic piping is adopted statewide.

2007 California Plumbing Code

Installation Standard

ABS BUILDING DRAIN, WASTE, AND VENT PIPE AND FITTINGS

IAPMO IS 5-2003

2.2.3 Exposed Piping

Piping shall not be exposed to direct sunlight. Exception: Vent piping through roof. Plumbing vents through roof, exposed to sunlight, shall be protected by water base synthetic latex paints. Adequate support shall be provided where ABS piping is exposed to wind, snow, and ice loading.

Installation Standard

PVC BUILDING DRAIN, WASTE AND VENT PIPE AND FITTINGS

IAPMO IS 9-2003

2.3.3 Exposed Piping

Piping shall not be exposed to direct sunlight. Exception: Vent piping through roof. Plumbing vents through roof, exposed to sunlight, shall be protected by water base synthetic latex paints. Adequate support shall be provided where PVC piping is exposed to wind, snow and ice loading.

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. . . but I'm not entirely convinced that UV is going to damage it to the extent where it's "brittle" as you've stated. I inspected a 10-year old PVC roof the other day that's not coated with any inhibitors of any kind and it seems to be able to handle the UV just fine.

What standard are you using?. . .

Both Washington & Oregon have exactly the same requirements as Cali. They apply to both PVC and ABS pipe. Neither is supposed to be left exposed to sunlight. In WA, you'll find the rule at the end of the plumbing code, under the "Installation Standards" section. The section numbers are 2.2.3 in both the ABS and the PVC standards.

Of course, this rule is routinely ignored at rain drains and at plumbing vents.

- Jim Katen, Oregon

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Of course, this rule is routinely ignored at rain drains and at plumbing vents.

Jim,

Do you write it up, or have you ever considered writing it up?

Brandon

Sorry to barge in to your question to Jim but I do litigation work so I'll always write it up.

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