Pipe size to shower


Old 03-30-19, 06:39 AM
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Pipe size to shower

Im putting in a walk in shower using Delta products which all use 1/2 plumbing, including inlets. Im using Pex with home runs to a 3/4 x 1/2 manifold (3/4 in, 1/2 out). I read somewhere that I should run 3/4 hot n cold to the shower and then reduce to 1/2 at the mixer valve. This makes no sense to me. Why would I run 3/4 when the valves and sprays are 1/2?

Old 03-30-19, 09:14 AM
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Why would I run 3/4 when the valves and sprays are 1/2?

No good reason I can think of, never seen it done that way before. A good reason to use 1/2" pipe is to reduce the time and waste of water trying to get hot water to the shower faucet.
Old 04-01-19, 11:03 AM
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Agreed, 1/2" is quite sufficient for any standard shower/tub (as long as you're not installing a high-end multi-head shower).
Old 04-01-19, 01:18 PM
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I have 3/4" PEX trunk lines in my house with individual 1/2" lines T off for each fixture. I've never had any issue with pressure or flow volume but all my fixtures are modern low flow style.

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