Which of the following is not a requirement for a vent stack in a residential building?
- A minimum of two vent stacks are required.
- BVent stacks must be installed at least 6 feet above the highest fixture.
- CVent stacks must be installed at least 3 feet above the roof.
- DVent stacks must be installed at least 2 feet above the highest vented fixture.
Exam tip
Be aware of the specific requirements for vent stack installation heights and the number of vent stacks is not a fixed rule.
Why A is correct
Section P1103.1 of the 2024 International Residential Code does not specify a minimum number of vent stacks. However, it does require that vent stacks be installed at least 6 feet above the highest fixture, at least 3 feet above the roof, and at least 2 feet above the highest vented fixture.