Where should a gas vent not terminate when extending through an exterior wall?

A gas vent should not terminate below eaves or parapets due to safety and structural concerns. Vents are designed to safely expel exhaust gases from appliances, and terminating them in areas where they can become obstructed can lead to harmful backdrafting or the release of toxic gases into the atmosphere.

When vents terminate below eaves, especially in cold weather, the gases can condense and create ice, which could block the vent and prevent proper functioning. Additionally, proximity to other structures or overhanging eaves can pose risks of fire or improper ventilation. Therefore, it is crucial to ensure that gas vents are routed and terminated in a manner that promotes safety, compliance with codes, and effective operation of the gas appliance.

The other scenarios outlined—such as terminating adjacent to the wall, below a window, or above the roof—are typically acceptable based on local codes and regulations, as they provide necessary clearance and reduce the risk of blockage or hazardous conditions.