Framing

Gable Wall Top Plate Length

With this calculator, you can calculate the length of a plate that runs diagonal to the bottom plate using the slope ratio and the length of the bottom plate.

Calculate the length of the diagonal plate on a gable wall using the bottom plate length and the slope ratio.

Gable Wall Top Plate Length

Diagonal Plate Length

Calculation

the slope ratio (the amount of rise in 12 inches of run)
the length of the bottom plate in feet and or inches
the denominator of the fraction used in the result

Results

length of the diagonal plate in inches
the length of the diagonal plate in feet and inches

Example calculation:

5: 12 slope ratio
bottom plate length = 15' - 5" = 185 inches
Calculate the slope factor from the slope ratio;
To be able to do this, you need to know the formula that converts the slope ratio to a slope factor.
Slope Factor Formula = √rise*rise+run*run/12

Plug in the values: √5*5+12*12/12 = 1.083333333.
Multiply the bottom plate length by the slope factor to get the diagonal plate length;
185 *1.083333333 = 200.4166667 = 200 7/16 inches.
The diagonal plate length is 200 7/16 inches or 16' - 8 7/16"

Framing

Gable Wall Top Plate Length

Diagonal Plate Length

Results:

Calculation

Results

Example calculation:

Wall and Floor Framing