Roof Rafter Collar Ties

Collar ties provide additional structural support for wood framed roofs that bear the weight of clay or concrete roofing tiles.

Roof rafter collar ties.

This article describes and illustrates the different types of support that prevents roof sagging and wall bulging at buildings including definitions of collar ties rafter ties and structural ridge beams. 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 collar ties are necessary to prevent separation of the roof at the ridge due to wind uplift. Collar ties collar ties are connections between opposing rafters at the upper one third of the roof frame area just below the ridge and they are required at a 48 4 maximum spacing which is every other rafter of a 24 on center spacing and every third rafter with 16 on center spacing. This article excerpts from provides copies of roof framing suggestions from canadian building codes and the cmhc wood frame house construction guide.

Framing any roof but particularly a gable roof low slope roof and cathedral ceilign roofs requires collar ties rafter ties and possibly a structural ridge beam to support the roof and to. There are some exceptions however when collar ties might be useful even in a conventional attic roof. Collar ties rafter ties tension beams structural ridge beams. For example very long rafters in a relatively steeply pitched roof slopes above 6 12 for instance may benefit from a stabilizing effect if adequately connected collar ties are installed on every rafter pair.

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 may take up space in the attic of your home but they are there for a reason. The rafter ties are incorrectly labelled as collar ties. The upper collar tie does not experience the tension that the lower rafter tie is resisting if that tension is resisted in the upper third the roof is probably on the ground.

Some of these can support the roof and prevent ridge sagging and wall spreading. The prescriptive provisions of the building code require rafter ties on each rafter pair and collar ties every 4. Roof framing suggestions canadian guidelines. The collar ties are used to strengthen the roof rafters to prevent them from buckling or sagging under the weight of the roof.

In this case the collars.