Horizontal Piping

Section 890 Section 890.930  Horizontal Piping a)         Support.  Horizontal piping shall be supported at sufficiently close intervals to keep the piping in alignment and prevent sagging. b)         Cast Iron Soil Pipe.  Where joints occur, suspended cast iron pipe shall be supported within 18 inches of each hub or joint and at not more than 5 foot intervals; however, pipe exceeding 5 feet in length may be supported at not more than 10 foot intervals.  Hubless or compression gasket joints must be supported at least at every other joint except that when the developed length between hubless or compression gasket joints exceeds 4 feet, supports shall be provided at each joint.  Supports shall be placed on or immediately adjacent to the joint.  Suspended pipes shall be braced to prevent horizontal movement. c)         Threaded Pipe.  Threaded pipe 1½ inches and larger shall be supported at least at 12 foot intervals; smaller pipe (e.g., 1¼ inch pipe) shall be supported at least at 8 foot intervals.  Supports shall be of ferrous material. d)         Copper Tube.  Hard drawn copper tube shall be supported at least every 8 feet for one inch and smaller tube, and at 10 foot intervals for larger sizes.  Annealed copper tubing shall be supported at least every 8 feet.  Supports shall be of copper material or other material of sufficient strength to support the tubing and which will not react with copper piping material. e)         Lead Pipe.  Lead pipe shall be supported for its entire length. Supports in contact with the pipe shall be of lead or softer material. f)         Plastic Pipe.  Hangers and straps shall not compress, distort, cut or abrade the piping and shall allow free movement of the pipe.  Wire pipe hooks shall not be used to support plastic pipe.  Restraining joints and expansion joints shall be installed as required.  All horizontal piping shall be supported at intervals of not more than 4 feet, and at ends of branches, and at changes of direction or elevation.  Trap arms in excess of 3 feet shall be supported as close as possible to the trap.