Does the orientation of a supply tee matter for water flow rate?

[Temp945]

Hi all,

I am installing my shower valve and volume controls and need to use a tee to split the supply after the thermostatic valve to provide service to the shower head and hand shower.

Does the orientation of the tee matter if I want the shower head and hand shower to have the same flow rate when both are turned on?

The tee can be oriented so that the water flows straight through to the showerhead and branches off to the hand shower, like so:



My intuition tells me that the lower resistance of the straight-through path to the shower head would result in the shower head having greater flow than the hand shower when both are turned on, but I don't know this for sure.

The tee can also be oriented so that the water hits the "dead end" of the tee and flows left to the shower head and right to the hand shower, like so:



This orientation seems like it would result in equal resistance to both the shower head and hand shower, which would result in equal flow, but installing the tee in the latter ("dead end") orientation will require me to make several 90-degree bends in the supply line to make the connections thereafter, so if it doesn't matter, I'd prefer to go with the first option.

Thanks for reading!

 

[Reach4]

Does the orientation of the tee matter if I want the shower head and hand shower to have the same flow rate when both are turned on?

The flows are much more likely to be limited by the respective showerheads. Some showerheads have a flow control that tries to keep the same flow when the incoming pressure changes.

Your analysis is valid in theory, but the effect of the differences in tee orientation are going to be too small to measure for normal showerheads.

 

[Sponsor]

 

[Sylvan]

Normally under good plumbing practices we never use the bull of a tee to supply water as it has to much friction loss going through two 90 Deg angles

Going straight to the shower head is the way to go

 

[Terry H]

Probably considering the location it won’t hurt anything but as been noted not ideal if you were say plumbing a whole house or running a bathroom off that configuration.

 

[Temp945]

Thanks guys - I'll install the tee so that it flows straight through to the shower head.

Much appreciated!