Sprinkler main size???

Discussion in 'Irrigation' started by Dafan6891, Aug 10, 2004.

  1. Dafan6891

    Dafan6891 LawnSite Member
    Messages: 15

    Hi everyone I'm new here, so forgive me if I don't use the right terms. :rolleyes: . A friend of mine is going to install a sprinkler system for me, and to keep cost down I will be helping do some of the bull work. I presently have city water with a 1" meter in a pit at the street, with 1" poly pipe feeding the house. He wants me to run 1 1/2" sch40 pipe from the basement main line (1")to about 10' away where the manifold of valves will be located outside. Why such big pipe for a short distance? He said he will be using 1" zone valves and 1" poly pipe for laterals(?). I don't want to question his expertise, so I figured someone could help me here.:confused: Sorry if I rambled on!! Dave

    CRUZMISL LawnSite Member
    from zone 6
    Messages: 186

    I'll take an educated guess and say there is no reason to use a larger pipe that what supplies the water. No matter how big you go after the supply line you'll still be limited to the capacity of a 1" pipe.

  3. aquamtic

    aquamtic LawnSite Senior Member
    Messages: 303

    I'll second that! Unless you were running that line over 100' to prevent friction loss. Stick to all 1" Pipe and backflow and also stay away from the PVC. Poly is all you need
  4. HBFOXJr

    HBFOXJr LawnSite Bronze Member
    Messages: 1,712

    1" pvc has less loss than 1"poly at equal gpm. Thre is no justifiable reason I know to go to 1.5" pipe for such a few ft.
  5. jerryrwm

    jerryrwm LawnSite Bronze Member
    Messages: 1,274

    Agreed. 11/2" is a bit of overkill for the small amount of pressure that may be saved.

    I prefer the PVC for setting a manifold for the rigidity, but then down here in South Texas we don't get down to freezing but about 2 days a year and then it pops right back to the 90's. (remembers when we had 2" of snow in 1972 - closed the schools that day!)

  6. You have a lessor chance for the 1.5"' pvc pipe to freeze than the 1" size, but i would stay with the 1"' size, and I Hate poly pipe!!!!!!!

Share This Page