[Leo55]

Hey everyone.

I'm replacing the plumbing in a small 1 story house with PEX. I'm planning to do a manifold with home runs. Do you guys run 1/2" to every fixture, or do you run 3/8" at times? I have seen/read that some people use 3/8" at times, but it seems so small to me. But I am also not experienced with PEX. I can see a smaller diameter being an advantage particularly with hot water.


Thanks for any thoughts.

 

[scfreeman66]

I just finished my house. I ran 1/2" to each individual fixture. The flow rate is sufficient. I think 3/8" would reduce that quite a bit.

Sent from my moto g(7) optimo maxx(XT1955DL) using Tapatalk

 

[Old Thomas]

I use 1/2” as a minimum size. At $28 for a 100 foot roll, I don’t see a reason to stock all the parts in 3/8”.

 

[Bud9051]

When I made the decision to go pex I looked at the fittings and they were smaller. A 1/2" fitting was only 3/8" ID. I don't know what the resulting size of a 3/8" fitting would be.

Bud

 

[Leo55]

Thanks for the thoughts. Yeah, I'd read that 3/8" could be used for some fixtures like toilets because you don't care that much about how fast a toilet fills. Or in certain instances you might be able to do 3/8" for a hot water line, as it would mean less water needs to be purged before you get hot water at the tap. I was contemplating the possibility for a half bath, I guess, because that sink would never get used for anything but hand washing. I don't think I'd do it for the toilet, though, because I actually do kind of care how fast it fills. Who wants to be the guest at your house and have to take a big hairy then wait several minutes between flushes? Plus if it fills faster I guess I don't see that as wasting water---it would just shut off faster, right?

There was a document that someone linked me to about designing pex systems, and one of the things they cautioned against was oversizing lines. I guess it made me think about some of the stuff I'd seen about 3/8", and I was curious to hear what people with more knowledge would say.

 

[rjniles]

When I re-plumbed with PEX I used 3/8 for toilets, vanities and ice maker.

BTW I plumbed the ice maker from the hot supply. The ice maker does not draw enough water to actually get any hot water but the water heater precipitated out some of the minerals in my very hard well water.