I have a copper water supply line coming through the crawlspace and someone had made a repair and had converted the 3/4" copper to 3/4" PVC sch. 40. A few feet later he glued on a PVC main water shut off valve. Is this acceptable?
ps. I wish I knew how to insert an image, maybe someone on the forum can tell me.
Gary
Schedule 40 pvc is not allowed as a water supply pipe within the dwelling.
What about after main shut off valve? Can you use PVC for distribution piping?
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I could be wrong but I think only members can insert a picture
No schedule 40 pvc for supply piping within the dwelling. As I understand it, the crawl space is within the dwelling as well.
Since when can’t you use PVC 40 for cold water supply lines in a house?
CPVC is typically used within a dwelling because of it’s higher heat resistance. PVC sch 40 can be used as a cold supply line from Muni meter to dwelling entrance shutoff without issue.
This is exactly correct. The difference is water service piping versus water distribution piping. Service ends at the main shutoff.
Good info!
Correct, for both hot and water
There is absolutely no reason you can’t use PVC 40 for cold water distribution after the meter as well.
You can use PVC 40 for cold water distribution piping as well.
Except that it’s not allowed by “most” local codes as “distribution pipe”.
Check your local AHJ or codes for specifics.
How do you know this…that most don’t allow it? And for what reason?
Most States either utilizing the International Residential Code, or using it as a model code.
Specifically, Table P2906.4 which lists PVC as an acceptable water service pipe, and Table P2906.5 which omits PVC as an acceptable water distribution pipe.
Weird. They allow it for one, and not the other - I wonder why?
As alluded to earlier, I suspect it has to do with temperature.
PVC is suitable for cold (or rather, “non-hot”) water. It deteriorates when exposed to hot water.
Could be PVC, even when used for cold water applications, would be exposed to higher temperatures at hot water heaters, shower bodies, tempering valves etc.
Or it could be that they didn’t trust the average plumber to use PVC for cold and CPVC for hot 
I realize the hot water issue & that’s not what I was saying. 
That makes some sense, but I seriously doubt it’s going to get that hot to the point of warping/melting/distorting it. I would have a hard time “calling out” PVC 40 used for cold water distribution, despite what any list says.
Read this…
Good info, thanks Roy.
I wasn’t aware of the different NSF ratings.