What is the minimum height requirement for a class B vent?

The minimum height requirement for a Class B vent is indeed 5 feet. This regulation is in place to ensure proper draft and ventilation for the exhaust of gases from appliances, which is crucial for safety and efficiency. The height helps prevent downdrafts that could cause harmful gases to enter the living space and ensures that the vent meets the minimum standards set by codes and guidelines such as those from the National Fire Protection Association (NFPA) or local building codes.

In practical terms, having this requirement helps ensure that the vent draws air correctly, allowing appliances to operate efficiently while minimizing the risk of carbon monoxide build-up or other hazardous conditions. Lower heights may not sufficiently disperse exhaust gases safely away from the building, which is why meeting or exceeding this 5-foot minimum is essential.