503.6.4 Gas vent terminations.
FGC § 503.6.4
A gas vent shall terminate in accordance with one of the following: 1. Gas vents that are 12 inches (304.8 mm) or less in size and located not less than 8 feet (2438.4 mm) from a vertical wall or similar obstruction shall terminate above the roof in accordance with Figure 503.6.4.
2.Gas vents that are over 12 inches (304.8 mm) in size or are located less than 8 feet (2438.4 mm) from a vertical wall or similar obstruction shall terminate not less than 2 feet (609.6 mm) above the highest point where they pass through the roof and not less than 2 feet (610 mm) above any portion of a building within 10 feet (3048 mm) horizontally.
3.As provided for direct-vent systems in Section 503.2.3.
4.As provided for appliances with integral vents in Section 503.2.4.
5.As provided for mechanical draft systems in Section 503.3.3.
6.As provided for ventilating hoods and exhaust systems in Section 503.3.4. However, such constructions do not include chimneys or other vents, or open structural framing. The vent shall be as high as such construction which is located beyond 10 feet (3048 mm) from the vent and up to and including the distance determined by the following formula: D = 2 √ A(Equation 5-2) where: D=Distance, in feet, measured from the center of the vent outlet to the nearest edge of the construction.A=Free area, in square inches, of vent flue space. Roof SlopeH (min) ftRoof SlopeH (min) ftFlat to 6/121.0Over 6/12 to 7/121.25Over 7/12 to 8/121.5Over 8/12 to 9/122.0Over 9/12 to 10/122.5Over 10/12 to 11/123.25Over 11/12 to 12/124.0Over 12/12 to 14/125.0Over 14/12 to 16/126.0Over 16/12 to 18/127.0Over 18/12 to 20/127.5Over 20/12 to 21/128.0 For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm. Figure 503.6.4Termination locations for Gas Vents with Listed Caps 12 Inches or Less in Size at least 8 Feet from a Vertical Wall
