Roof Rafter Tie

Contrary to popular belief collar ties are not there to support rafters or to keep walls below from spreading under the weight of the roof.

Roof rafter tie.

Contrary to popular belief collar ties are not there to support rafters or to keep walls. High horizontal ties in the upper third of the roof under compression definition of mid span rafter ties. Located horizontally in the middle of the rafter s run or horizontal span neutral. Truss and rafter tie downs are used for wood construction and wood framing projects.

In most homes the ceiling joists also serve as the rafter ties. Moving the rafter ties up only 16 inches from the plate the maximum allowed by code increases the tie force from 1 440 pounds to 2 160 pounds. Located in the bottom. Compare this with a similarly framed 12 12 roof that has similar loads.

With the first collar tie in place you will follow the same procedure. Collar ties prevent uplift. Nail one end of the tie into the rafter with 3 inch nails. Where rafters are oriented perpendicular to the ceiling joists rafter ties should.

Rafter ties are always required unless the roof has a structural self supporting ridge or is built using engineered. Figure 2 is an illustration of a roof constructed using rafter ties. The tie will go from one side of a roof rafter to an adjacent rafter but on the opposite side. The tie force at the plate is 480 pounds and only 720 pounds when the ties are 4 feet up from the plate again the maximum allowed by code.

Step 4 continue installing collar ties. Simpson strong tie category roof truss and rafter connectors ties and straps for cold formed steel construction. This means that if you secure one end of the collar tie to the left side of a roof rafter you will nail it to the right side of the adjacent rafter. We detail these below.

Secure the opposite side in the same manner. Definition of collar ties. Illustration of roof with rafter tie. A tension tie in the lower third of opposing gable rafters that is intended to resist the outward thrust of the rafter under load.

Measure for each new collar tie.