3 of rise per 12 of run is the same as 1 of rise per 4 of run or 1 4 25.
Run and ise roof.
Total roof rise or change in elevation for a 38 degree sloping roof angle t with one giant rise or step of 7 8 feet to the center of the attic y 2 would have total a run x 2 of 10 feet.
Calculate the roof rise using the figures for unit rise and total run.
For example if the roof rises 4 feet and the span is 16 feet twice the run then the pitch is 4 16 or 1 4.
A 7 12 roof normally expressed as a ratio means that for every 12 inches horizontally the run your roof rises 7 inches.
The slope is the steepness of your roof and is the ratio between any two points on your roof.
Multiply your figure for unit rise by your figure for total run to get the total rise.
Using the example it would be six inches times 13 feet.
The rise is the distance from the top of the roof to the bottom.
Rise and run for your porch roof your roof s slope also called pitch is determined by the rise and run.
Here is an online rise and run calculator which helps to calculate pitch slope and angle with the help of rise and run values.
Pitch is the incline of the roof represented as the ratio of rise to the span twice the run.
The run is the distance from the outside of the wall to the inside of the ridge.
The horizontal change in distance or the horizontal distance covered by an un supported rafter or truss.
Why is the roof slope 25.
A 3 in 12 roof rises 3 for every 12 of run.