PVC for cold water distribution

[vegas paul]

While PVC is allowed for potable water supply, as soon as it enters the building (and becomes water distribution piping), PVC is not allowed. Of course, for hot water, this is understandable, but how would you feel about allowing PVC for a long stretch inside the building prior to encountering any water-heating system?

I have a renovation of an old (large) building that has 4" PVC supply and the designer wants to continue the 4" PVC for a long run into the building prior to branching off for individual units, which would be piped using CPVC.

The price difference between Schedule 80 PVC vs. CPVC is the driving factor.

Thoughts?

 

[globe trekker]

From the 2006 IEBC: Chapter 3, Section 302.9 - PLUMBING.[P]

"Additions, alterations, renovations or repairs to plumbing installations shall conform

to the International Plumbing Code without requiring the existing installation to comply

with all of the requirements of this code.........Additions, alterations or repairs shall

not cause an existing installation to become unsafe, hazardous or overloaded.

Minor additions, alterations, renovations and repairs to existing installations shall meet

the provisions for new construction, unless such work is done in the same manner and

arrangement as was in the existing system, is not hazardous and is approved."

I would not have any problem with using the existing pvc as an internal

distribution system and then, ...all new supply lines to comply with

"new" IPC construction requirements, except, ...I would ensure that the

existing 4" pvc piping was insulated if it is not in a conditioned

environment or if the area in which it is currently installed does not or

will not freeze, ...even without any heating.

.

 

[peach]

PVC has limits on pressure not just temperature.. I'd say no.. they need to use an approved material for water distribution.

 

[pwood]

if the existing installation was legally installed? pvc was never legally installed inside a building in these parts.

 

[skipharper]

At Richmond International Raceway they have a battery of about 20 water closets and the flush valves are served by a 3" pvc sch 40 main with 3 x 1 pressure tee's. Now most of us know why PVC is not allowed in the distribution system, and some of us know how to apply common sense. I'm sure I will get shelled on this reply!!! It's a case by case deal!!!

 

[vegas paul]

Peach - the distribution pipe pressure can't be any higher than the supply pressure, so PVC pressure limitations can't be the reason. Although the building entrance is USUALLY the threshold for when water supply becomes water distribution piping, the UPC definitions allow for this threshold to be within the building. I am NOT suggesting using PVC for distribution pipe, I am asking if the Schedule 80 PVC water supply can continue into the building for some length (possibly a long length in a big building) prior to branching off as water distribution pipe (using compliant materials).

 

[Uncle Bob]

Vegas Paul,

The simple answer is that it is a code violation. If you want to know why it is a code violation; just wait till Conarb posts; and he will provide links and proof that PVC breaks down and emits toxic material into the drinking water. And, everyone can make jokes about "the old boy" needs to take his meds; and we can go on poisioning our families.

The next time you go Walmart look at the shower curtians, cold drink coolers and other products; and see the new labels that say "NO PVC" used in the product.

It's sad when a retailer has to ban a material in their products before the the ICC, and code official who are charged with protecting our potable water supply system that our kids drink from; finally get the message.

Conarb has been posting factual information here and on the old BB for years; about the dangers of PVC materials; and everyone just chuckles and assumes that if everybody uses it; it must be ok..

You can always let them do it based on; "everybody else does",

Uncle Bob

 

[vegas paul]

Bob - Then why is it allowed for Water Supply piping?... that's my question. I'm not debating the "appropriateness" of PVC for use inside, but simply asking "If it's allowed for use up to and into the building, how far inside can the supply go prior to becoming water distribution piping?"

If it is unhealthy, then what magic takes place outside that makes it ok to use prior to entering the building?

 

[Uncle Bob]

Vegas Paul,

" Then why is it allowed for Water Supply piping? "

It's allowed because the manufacterers of bad, dangerous to the public, products have influence in the code writing process.

Unfortunately, the answer is that PVC should not be allowed to be produced; and, if produced should not be allowed to be used in our potable water system anywhere.

Peach mentioned the change in temperatures. PVC expands and contracts fairly easily; that's why manufacturers caution us to "snake" (not install in a straight line) pvc water pipe, when installing it; outside, underground. For lack of a better explaination; it will pull apart at the fittings; during this expansion and contraction, caused by ambient temperature changes; when under pressure; as in water piping.

Hope this helps,

Uncle Bob

 

[skipharper]

What Bob has stated I have never heard but find it interesting and will look when I am in the big box store the next time. Vegas Paul, the only reason pvc sch 40 pressure pipe is allowed for water service but not water distribution is the material is not approved for hot water. This is the one and only answer based on the IPC.