Roof Pitch Calculator Explained

Do you want to estimate the needed material for your roof? If so, you can count on the efficiency of roof pitch calculator. When measuring, make sure that you include the eaves covered region. An efficient calculator is very helpful when it comes to measuring the entire coverage of your home.

The roof pitch calculator works by calculating the angle, pitch, rafter lengths, and slope according to input of Rise and Run which are respectively denoted respectively by M and R.

In order to find out the finished height of the ridge beam, you have to add the Rise and the Run. So, how are you going to calculate the height? Start measuring the bird’s mouth working up to the calculated slop in accordance with the top of the rafter. So to say, the top of the ridge beam will be denoted by the formula M + Y.

Roof Pitch Calculator Explained

If you are being clouded by doubts when it comes to using roof pitch calculator, you have to ponder on the following details. Let’s take a closer look on the roof pitch calculator explained.


This is denoted by x/12 where in x refers to the measurement of the Rise for every twelve inches of run. Slope has wide range of applications. Say for instance, if you are working on roof framing, the slope is then essentially calibrated on speed squares. In roof framing, the slope is more called as pitch.


The roof’s angle is akin to its slope. The only difference is that it is represented in degrees instead of X/12. This is very relevant because there are some cases where in you have to cut bewel with the use of a circular swag saw that is not essentially calibrate with the use of the roof pitch style. Do take note that then it is calibrated in degrees.

Rafter Length

The rafter length refers to the length of line which is denoted by symbol L. You should know that this does not pertain to the actual length of the rafter. Instead, it refers to the length of a certain portion of the rafter. In case you are planning to come up with an overhang, it is advisable that you make the raft longer.


This pertains to the incline of the roof that’s being denoted as the ratio of rise to the span. To get the span, you just have to double the run. Say for instance, if your roof rises four feet and the span is sixteen feet,   the pitch will then be ¼.

If you calculate the length of the rafter from the center of the ridge beam, there is a need for you to subtract half of the ridge beam’s thickness from the rafter’s end. Say for example, if your ride beam measure 1.5 inches thick, there is a need for you to subtract ¾ of an inch from the overall length of the rafter.

For more information about roof pitch calculator, you might want to visit