Collar ties are necessary to prevent separation of the roof at the ridge due to wind uplift.
Roof rafter collar ties.
Rafter ties resist the forces caused by gravity loads that would otherwise cause the roof to pancake and push out the sidewalls.
By upper third here we mean one third of the length of the rafter from ridge to top plate.
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.
Collar ties attach between every other pair of opposing rafters at.
Collar ties may take up space in the attic of your home but they are there for a reason.
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.
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.
The collar ties are used to strengthen the roof rafters to prevent them from buckling or sagging under the weight of the roof.
A tension tie in the upper third of opposing gable rafters that is intended to resist rafter separation from the ridge because of wind or unbalanced roof loads.