What is the minimum size for collar ties?

The minimum size for collar ties is 1"×4". Collar ties are horizontal members that help to prevent the rafters from spreading apart under load, particularly in roofs with a slope of 4:12 or greater. The 1"×4" size provides adequate strength and support for this purpose, as it can effectively bear the loads typically encountered in residential construction.

Using smaller dimensions, such as 1"×2" or 1"×3", would not provide the required structural integrity to prevent the rafters from sagging or moving out of alignment under weight, particularly in areas experiencing snow loads or high winds. Therefore, the 1"×4" dimension is the industry standard, ensuring that the collar ties are robust enough to perform their intended function in the roofing system.