What is the Best PEX System Out There (to put in an attic)?

[RogerPDX]

Presently, I have 1/2" pex coming into my house from my well pump house. The water is distributed to all the fixtures via 1/2 pex. Would I be better off bringing in the water via a new 3/4" line to a manifold that would then distribute 1/2" lines to my fixtures? Would I notice any difference with a new 3/4" 'main' line vs a 1/2" main line like I already have?

 

[Jadnashua]

1/2" main line is totally inadequate, especially in pex! Unless you have a VERY slow recovery well and a big tank, you really should probably have something closer to 1 to 1.5" from the pump into the house. This is not my area of expertise, but 3/4" copper, which is closer to 1" pex is probably the smallest line you should have from the pump into the house. Someone else will comment. 1/2" pex is only good for about 5gpm, and anything other than a single point of use, 1/2" coming in would cause the flow to drop considerably.

 

[Sponsor]

 

[RogerPDX]

Our well is pretty bad, and yes, we have a big tank. Originally I put 1/2" in because of this. When I think about it, it seems that 1/2" and 1/2" to all the faucets would be no different than 3/4" in & 1/2" to all the fixtures. Same with 1" in and 1/2" to all the fixtures.

 

[Jadnashua]

That's true if you use a branch and trunk system, but not if you use a manifold. There, the manifold would be fed with a larger line so that you could still maximize the flow on each branch. Often with a branch and trunk system, the trunk is larger so that each branch can still have decent flow. 1/2" pex feeding into a whole house would be pretty pathetic by modern standards.

If your well can only provide a few gpm, then you'd need a really large storage tank, and the outlet from it would want to be larger.