Collar ties should be installed on rafters not supporting a ceiling that are 16" OC should have a collar tie installed on______?

Collar ties are essential structural components in roof framing, particularly for roofs that do not have a ceiling below. Their primary function is to prevent the rafters from spreading apart under load, such as snow or wind. When rafters are installed 16 inches on center (OC), the recommendation is to install collar ties on every fourth pair of rafters. This strategic placement helps maintain structural integrity without overcrowding or overbuilding the system.

Spreading the collar ties evenly at this interval allows for adequate tension across the roof structure, promoting stability while minimizing material use and labor. Each fourth pair provides sufficient reinforcement to resist lateral thrust, especially in cases of high wind or heavy snowfall. By following this guideline, builders can ensure that the roof remains secure and functional over time.