Skip to main content

Plumber Red Seal · Question

A plumber is designing the venting system for a multi-story commercial building. A 100 mm soil or waste stack typically requires what minimum nominal pipe size for its stack vent, according to the NPC?

The National Plumbing Code of Canada generally requires that a stack vent, and any vent pipe that extends through the roof, is not less than 65 mm nominal pipe

Start free practice for Plumber Red Seal

177 questions · no signup required · 40 free questions per day

Start Practice →

Question: A plumber is designing the venting system for a multi-story commercial building. A 100 mm soil or waste stack typically requires what minimum nominal pipe size for its stack vent, according to the NPC?

Answer options:

  • 38 mm
  • 50 mm ✅ 65 mm
  • 75 mm

Correct answer: 65 mm

Explanation: The National Plumbing Code of Canada generally requires that a stack vent, and any vent pipe that extends through the roof, is not less than 65 mm nominal pipe size where the soil or waste stack is 100 mm in size. This ensures adequate air circulation and prevents frost closure at the roof terminal.

Start free practice for Plumber Red Seal

177 questions · no signup required · 40 free questions per day

Start Practice →

More about Plumber Red Seal

Related Questions

More for Plumber Red Seal candidates

Ready to practice?

Free, no signup required. Build a wrong-question list as you go.

Start Free Plumber Red Seal Practice →

Related courses

Other Canadian certifications candidates often prepare for alongside this one.