What is the function of collar ties in roofing?

Collar ties play a crucial role in roof construction by helping to maintain the structural integrity of the roofing system. Their primary function is to prevent the roof rafters from sagging and spreading apart due to the weight of the roofing materials or other loads. By connecting opposing rafters, collar ties create a brace that limits the downward movement and lateral expansion that can occur over time. This is especially important in steeply pitched roofs where the forces acting on the rafters can lead to structural issues if left unmitigated.

In contrast, the other options focus on different aspects of roofing support and could lead to confusion regarding can similar components in roof framing systems. For instance, while collar ties do offer some connection to the floor or ceiling areas, their major function pertains to the roof rafters rather than directly to the attic floor. Similarly, the primary purpose of supports in roofing systems encompasses functions such as load transmission or directly supporting the roof sheathing, which are typically provided by other components like ridge beams or ceiling joists. Thus, understanding the specific role of collar ties helps clarify their essential contribution to stabilizing rafters in roof structures.