CSLB C-36 Plumbing ContractorRough-in PlumbingHard
A plumbing contractor is installing a new drain, waste, and vent (DWV) system in a multi-story commercial building. The contractor is preparing to install a vertical portion of a soil or waste stack. How is a 'vertical pipe' defined in the context of the California Plumbing Code for DWV systems?
- AAny pipe or fitting installed in any direction with a fall greater than 45 degrees from the horizontal.
- BAny pipe installed at an angle between 60 and 90 degrees from the horizontal.
- CAny pipe with a slope greater than 1/2 inch per foot.
- DAny pipe that rises perpendicular to the floor it serves.
Show answer & explanationAnswer & explanation
Correct answer: A. Any pipe or fitting installed in any direction with a fall greater than 45 degrees from the horizontal.
According to the California Plumbing Code (CPC), a 'vertical pipe' is defined as any pipe or fitting installed in any direction with a fall greater than 45 degrees from the horizontal. This clear definition helps distinguish between horizontal and vertical drainage components.
Why the other options are wrong
- B. This definition is too restrictive; the code uses a broader 'greater than 45 degrees' criterion.
- C. This defines a steep slope, but not the specific code definition for a 'vertical pipe' which is angle-based.
- D. While often perpendicular, the code definition is based on the angle of fall, not relative to the floor.
Vertical Pipe Definition (DWV)
The plumbing code's precise definition for a pipe segment that is considered 'vertical' within a drainage, waste, and vent system.
- Distinguishes from horizontal pipes for sizing and venting.
- Based on the angle of fall from the horizontal plane.
- Impacts fitting selection and installation rules.
Memory trick: Vertical piping falls more than forty-five; otherwise, horizontal it thrives.