Inspectors should check for chimneys that terminate less than how many feet above the highest point they pass through the roof surface?

Chimneys must terminate at least three feet above the highest point they pass through on the roof to ensure proper drafting and to prevent the potential for harmful gases, such as carbon monoxide, from entering the living space. This height requirement is crucial for effective ventilation, as it helps to create a sufficient upward exhaust flow for smoke and combustion gases, minimizing the risk of backdrafting.

In addition to the three feet requirement, the National Fire Protection Association (NFPA) and other building codes recommend that the height of the chimney should be measured not only in relation to the roof it exits but should also take into account the distance from nearby structures or trees. This is to ensure that the exhaust does not come in contact with or is obstructed by nearby structures, providing an added layer of safety.

The specific requirement of three feet is a widely recognized standard in chimney construction and inspection practices. Maintaining this height is essential for homeowner safety and compliance with established codes.