Spacing for pipe supports depends on the material used (see chart below).

Drainpipe Support
Drain Lines Max. Horizontal Spacing Max. Vertical Spacing
ABS and PVC 4 ft. 10 ft.
Cast iron 5 ft. (Max. support may be increased to 10 ft. for 10-ft. lengths of cast-iron pipe) 15 ft.
Copper or copper alloy (1 1/2 in. and larger) 10 ft. 10 ft.
Copper pipe must be supported with hangers that do not promote galvanic action, which will cause corrosion. Do not use copper strapping to support cast-iron drain lines.

Support materials. Wire or metal plumber’s tape is not recommended for pipe support, and may be restricted by code for plastic drain lines.

When hanging pipe, best practice calls for using a solid material, such as notched 1-by or approved pipe hangers from a plumbing supply house (see illustration below).


A flexible support, such as wire, should not be used to support plastic drain lines. Instead, use a notched 1-by wrapped with rubber or other insulation, as shown here.
A flexible support, such as wire, should not be used to support plastic drain lines. Instead, use a notched 1-by wrapped with rubber or other insulation, as shown here.

Solid hangers resist upward thrust and vibration, thereby providing more secure support, while also helping to quiet drain lines. Wrap the pipe with insulation at each pipe support to further dampen vibration.


Visit the JLC Field Guide  for a professional reference guide on Plumbing  > Drains.