Floor drain calculations

Discussion in 'Plumbing Products' started by britkath, Mar 17, 2014.

Help Support Plumbing Forums by donating using the link above.
  1. Mar 17, 2014 #1

    britkath

    britkath

    britkath

    Active Member

    Joined:
    Oct 2, 2013
    Messages:
    27
    Likes Received:
    2
    Location:
    ,
    To calculate the GPM capacity of a floor drain, I found the following equation:
    Q = 448.2 Cd A 2gh where Q = Flow Rate (Gallons per Minute)
    Cd = Discharge Coefficient (Typically 0.6)
    A = Open Area of Grate (ft2)
    g = Acceleration (32.2 ft/s2)
    h = Head Above the Floor (ft)

    What is meant by head above the floor for h? the floor drain is flush with the floor.
     
  2. Mar 17, 2014 #2

    IFIXH20

    IFIXH20

    IFIXH20

    HERE TO HELP Professional

    Joined:
    Mar 18, 2012
    Messages:
    948
    Likes Received:
    236
    Location:
    ,
    If I'm not mistaken the head above the floor is the amount of water buildup on the floor. Engineering mumbo jumbo.
     
  3. Oct 11, 2014 #3

    wyrickmech

    wyrickmech

    wyrickmech

    Member

    Joined:
    Oct 10, 2014
    Messages:
    5
    Likes Received:
    0
    Location:
    ,
    Get a code book,each size has a dfu (drainage fixtures units)which is how you size it.
     

Share This Page