Roof Construction Collar Ties

This balances the construction and makes it look beefier.

Roof construction collar ties. The 2015 international residential code does not require collar ties or collar beams. They still tie the rafters together but they no longer form the low flat barrier that ceiling joists do. First referenced in the irc in 2006 collar ties had been required long before that in the southern standard building code and in the high wind provisions of the uniform building code. The collar ties are used to strengthen the roof rafters to prevent them from buckling or sagging under the weight of the roof.

By upper third here we mean one third of the length of the rafter from ridge to top plate. Collar ties may take up space in the attic of your home but they are there for a reason. Often collar ties are structural members but they may be used simply to frame a ceiling. We include sketches of collar ties rafter ties and structural ridge beams as well as illustrations of collapsing and collapsed structures where these roof rafter ties were lost or omitted.

In this how it works article managing editor debra judge silber explains the role of collar and rafter ties in the framing of a roof. A collar tie is a tension tie in the upper third of opposing gable rafters that is intended to resist rafter separation from the ridge beam during periods of unbalanced loads such as that caused by wind uplift or unbalanced roof loads from snow. A collar tie is a horizontal member between two rafters and is very common in domestic roof construction. This is especially important if the home is in the northern climates where snow accumulates on roofs or if there are multiple layers of roofing materials.

Collar ties collar ties are horizontal framing members that are essentially ceiling joists that have been moved upward to span the distance between the rafters higher than the top of the walls. The much maligned collar tie. Collar ties are necessary to prevent separation of the roof at the ridge due to wind uplift. The international code council icc is a non profit organization dedicated to developing model codes and standards used in the design build and compliance process.

The last roof framing member to discuss is the collar tie also called a collar beam. A collar tie is a horizontal roof rafter compression connector that is located in the uppermost third of the span of a pair of opposed sloped or gable roof rafters. In collar tie roof the horizontal tie is raised up from the feet of the rafters to the almost middle of the rafters. The international codes i codes are the widely accepted comprehensive set of model codes used in the us and abroad to help ensure the engineering of safe sustainable affordable and resilient structures.

In a frame like this the remaining collar ties are often doubled up putting one 2x on each side of the rafter.