Final answer:
If the dimension of the chimney parallel to the ridgeline exceeds 30 inches and does not intersect the ridgeline, a chimney cap must be installed to maintain efficiency and safety.
Step-by-step explanation:
If the chimney has a dimension parallel to the ridgeline greater than 30 inches and does not intersect the ridgeline, a chimney cap must be provided.
A chimney cap is a cover that is placed on top of a chimney to prevent debris and animals from entering the chimney. It also helps to prevent rain and snow from entering the chimney and causing damage. By installing a chimney cap, it helps to maintain the efficiency and safety of the chimney.
For example, in the case of a wood stove or other efficient device that prevents most heat from just escaping through the chimney, a chimney cap can help to maintain the upward airflow and prevent downdrafts that may occur due to strong winds.