Running pex for washing machine from main water line vs. branch ?

[MarsellusWallace]

Hey all,

Looked around for this issue but I'm seeing mostly discussions on 'home runs'..

I'm moving my washing machine to the utility room of my basement. If I want to run hot and cold water lines for the washer/sink, does it matter if the PEX ties in to the main water lines (water furnace and street line) or can I tap into the lines that are already branched and running to a second floor bathroom? I know connections to the main are preferred, but they're both in close proximity (4ft apart), so I'm wondering if that means anything in terms of affecting pressure?

Tapping into the bathroom lines would be a more convenient position for soldering the sweat adapters and less pex bends. I'm not sure if this would affect pressure in case 2nd floor shower and washer are used at the same time? (Not sure if there would be a bottleneck?)


Appreciate any input!

 

[Breplum]

tapping off 1/2" lines would likely cause pressure drop if other fixtures are used simultaneously.

 

[Sponsor]

 

[John Gayewski]

You wanna connect to a 3/4" pipe for each. Preferably after everything else, which might give priority to other fixtures, but the pressure drop will be present no matter what.

 

[Jeff H Young]

What you are calling the branch to upstairs bathroom appears to be going elsewhere as well? if those are 3/4 copper (they dont look it) then sure B might be ok but I think more is going on and they are only 1/2 inch lines so Id connect at A