Fixture-Unit Requirements on Trap Sizes

Trap size and no. fixture units

The maximum number of fixture-units and trap sizes in drainage systems can be estimated with the table below.

No. of Fixture Units Trap Size
(in)
1 1 1/4
2 - 3 1 1/2
3 - 4 2
5 - 6 3
6 - 8 4

Search the Engineering ToolBox

Engineering ToolBox - SketchUp Edition - Online 3D modeling!

3D Engineering ToolBox - draw and model technical applications

Engineering ToolBox - SketchUp Edition - enabled for use with the amazing, fun and free Google SketchUp

Translate the Engineering ToolBox
About the EngineeringToolbox