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renos_gw

Loss of Water Pressure - 90 Deg Angles?

renos
13 years ago

Would anyone happen to have some insight into angles in copper piping and the imapct on water pressure? I am renovating my bathroom and in order to accommodate a 'niche' on the shower head wall (in between the head and the control fixture) the plumber routed the piping around the niche area. Meaning instead of a pipe straight up to the shower head he used a three(?) 90 deg angles.

No my building reversed their original approval and says I can't build the niche!

Would any one know if these angles will significantly affect the water pressure from the shower head? Should I consider removing that part of the tile and having a new pipe put in that goes straight up to the head? Thanks a million for any advice!

Comments (13)

  • zl700
    13 years ago

    You don't mention pipe type, pressure, distance, fitting type so I'll answer in generality.

    1/2" copper has a head loss of about 12' for 100' pipe at 3 GPM, which equals 5.19 PSI drop per 100'. 1 - 1/2" copper 90 = 1.5' of pipe in head loss.

    Short answer an extra 90 will cause about a 0.65 PSI drop, an extra foot of pipe will equal 0.27 PSI drop at a standard shower head, I doubt you will notice that.

  • renos
    Original Author
    13 years ago

    Thanks for both so much your comments. I'll try to get more information. This does involve 3 elbows instead of the straight line in the regular small copper piping (Hansgrohe fixture). I'm concerned though when you say I am 'renovating but creating a disaster'! Not sure what you mean by a membrane between the wall tiles and the studs. There is the 'wonder board I think? and then a big air space back to the back wall of the conpacter area (thus I thought I could build a niche there but the condo retracted their original yes to a no). Sorry but not being very technical in these areas I do try to do my due deligence but suspect I am somewhat at the mercy of the workers! Many thanks for your help!

  • hendricus
    13 years ago

    If the niche is out why not straighten out the pipes?

  • renos
    Original Author
    13 years ago

    Actually the wall behind the tub is closed and tiled so hard to get to it. However I may be replacing some tile in a strip about 12" to the left of the shower faucet so maybe the plumber can work through that. Will have to see. Thank you.

  • User
    13 years ago

    Pressure loss due to elbows is not the only issue you are potentially dealing with here. On their own, the additional elbows in the pipe will not cause any noticable pressure loss. However, when water flows through an elbow, the flow pattern is disrupted significantly and needs distance to smooth out again so as not to cause problem in your shower valve. For this reason, shower valves will specify the minimum length of straight pipe necessary before entering the valve. You need to look at the specs for your shower valve to ensure the last elbow is far enough from the valve. Otherwise you will have a problem with sporatic flow, the showerhead spitting water at you in spurts, inability to control temperature, all generally unpleasant, not to mention potentially damaging to your valve.

    As to the membrane davidro1 referred to: Waterproofing. You must have some waterproofing mechanism in a shower installation or it will leak into your walls. Wonderboard IS NOT waterproof.

  • zl700
    13 years ago

    Op said the pipe was the riser to the head.

  • User
    13 years ago

    Ah, yes, I missed that somehow. Oops

  • davidro1
    13 years ago

    hey renos, you better go web searching.

    "shower membrane"

    and learn fast.

    You have no waterproofing in your shower walls.

    There could be more bad news.

    Open a new thread about this when you have read a little.

    HTH

  • User
    13 years ago

    davidro1 - That is not necessarily true. OP may have seen waterproofing and just not known what s/he was seeing.

  • renos
    Original Author
    13 years ago

    Thank you all for your input. I know they used the wonder board on the walls and Laticrite on the floor and 6" up the walls outside of the tub. I don't recall any others special membrane in the tub area but I will check with the contractor. Also noted your comments about making sure the elbows work with the valve etc. so I will check this with the plumber too. Thanks again!

  • davidro1
    13 years ago

    renos,
    You need to know a lot more about "missing membrane" right now.

    Start a new thread immediately, with the appropriate subject line.
    Post whatever the contractor tells you he did.

    This thread is an old one, about a non-problem: elbows in the riser pipe.
    ((renos, it seems you didn't catch that it's not a problem.
    the posts made on
    Tue, Aug 31, 10 at 19:19 and
    Tue, Aug 31, 10 at 22:16
    annulled the statement about the possible problem.))

    A new thread will get eyeballs, from people who know membranes.
    Laticrete only six inches up, is so-so construction.

    Laticrete videos are on youtube.
    http://www.youtube.com/watch?v=lcA1AALeS_s

    Laticrete has a web site where you can read more.

    HTH !!

  • Joshua Murray
    3 years ago

    Bunch of BS. Unless you have pictures. Code says nothing about 90’s but 45’s work as well and if he is a “Plumber” 45s installed is still considered a Horizontal Run causing no pressure change. Hammer Arrestors on tub and shower valves Highly Recommended, Texas has the hardest codes in the nation. We’re also the only State that gets Tested and Licensed Not Certifying.

    Joshua Murray

    2105529967