G2 Gas Fitter Practice Exam

For a roof with a 10/12 pitch, what is the minimum vent height if there is a wall 4 feet high and 6 feet away from the vent opening?

1. 6 feet

2. 8 feet

3. 10 feet

4. 12 feet

The correct answer is: 10 feet

To determine the minimum vent height for a roof with a 10/12 pitch, it's important to understand how the pitch influences the angle of the roof and how this relates to the wall located 4 feet high and 6 feet away from the vent opening. A roof with a 10/12 pitch means that for every 12 horizontal units, the roof rises 10 vertical units. This gives an angle that needs to be considered when placing the vent to ensure it is adequately above any nearby obstructions, such as walls. In this scenario, the wall's height and distance from the vent must be evaluated to ensure that the vent outlet remains above any potential blockage caused by the wall. When considering the 6-foot horizontal distance from the wall and the height of the wall at 4 feet, you can visualize or calculate a right triangle. Using the pitch, the rise due to a 12-foot horizontal space is 10 feet. Given that the wall is 6 feet away, to find out how high the vent needs to be to ensure that it is above the wall while respecting the pitch, one needs to project the pitch line from the roof to determine the height. Calculating the height at that distance involves recognizing that at 6 feet