Vent Termination Too Close to Window
A two-story house has a 3-inch vent stack serving a bathroom group on the second floor. The vent terminates through the roof, but the homeowner complains of sewer odor near an operable bedroom window. The window is 4 feet below the vent termination and 6 feet horizontally from it. The vent pipe extends 6 inches above the roof surface, and the roof pitch is 4:12. The vent is located on the north side of the roof, and snow accumulation is common in winter. The local code requires vents to terminate at least 10 feet horizontally from any operable window, door, or air intake, and at least 2 feet above the roof surface if within 10 feet of the roof edge. The vent currently has a rain cap.
1. Does the current vent termination comply with the local code requirements? Explain why or why not.
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The vent termination does not comply. The local code requires a minimum horizontal distance of 10 feet from any operable window. The vent is only 6 feet horizontally from the bedroom window, which is less than the required 10 feet. Additionally, the vent must terminate at least 2 feet above the roof surface if it is within 10 feet of the roof edge. The vent is only 6 inches above the roof, and the roof pitch is 4:12, so the vent is likely within 10 feet of the roof edge (since the roof rises 4 units for every 12 horizontal, the vent could be close to the edge). However, the primary violation is the horizontal distance to the window. The vent must be relocated or extended to meet the 10-foot horizontal clearance.
2. What corrective actions would you recommend to bring the vent termination into compliance and address the odor complaint?
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To comply, the vent must be relocated so that it is at least 10 feet horizontally from the operable window. If relocation is not feasible, the vent could be extended vertically and horizontally to achieve the required distance. Additionally, the vent should terminate at least 2 feet above the roof surface if within 10 feet of the roof edge, and considering snow accumulation, increasing the height to at least 2 feet above the expected snow line is advisable. The rain cap should be checked to ensure it is not obstructing flow. Also, verify that the vent is not clogged and that the trap seals are intact. If the odor persists, a smoke test can identify other issues.