Roof Construction Collar Ties

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.

Roof construction collar ties.

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. By upper third here we mean one third of the length of the rafter from ridge to top plate. 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. The much maligned collar tie.

Collar ties may take up space in the attic of your home but they are there for a reason. Definition of collar tie in roof framing. 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. They still tie the rafters together but they no longer form the low flat barrier that ceiling joists do.

The collar ties can be wrapped with drywall or a higher grade of lumber can be used and left exposed. In a frame like this the remaining collar ties are often doubled up putting one 2x on each side of the rafter. A collar tie is a horizontal member between two rafters and is very common in domestic roof construction. Collar ties are necessary to prevent separation of the roof at the ridge due to wind uplift.

In collar tie roof the horizontal tie is raised up from the feet of the rafters to the almost middle of the rafters. This balances the construction and makes it look beefier. 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. Sagging rafters leaning walls collapsing roofs how defects in roof framing or damage to roof connections or structural members lead to building damage.

The last roof framing member to discuss is the collar tie also called a collar beam. 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. 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. 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 2015 international residential code does not require collar ties or collar beams.