How Do You Determine The Slope Of A Roof

Another way of stating this is that the roof has a rise of 5 and a run of 12.

How do you determine the slope of a roof.

So if your roof rises 4 inches for every 12 inches of horizontal length then the pitch of your roof is expressed as 4 12. Rise run pitch where pitch is expressed in percent. You can measure with twelve feet or twelve yards but in this article we will use twelve inches. Roof slopes are measured in units of twelves.

The way pitch also known as roof slope is measured is rise over run. Simply mark a level at 12 hold it perfectly level and measure from the roof surface to your 12 mark this. First enter the value of the rise and choose the unit of measurement from the drop down menu. Here are the steps to follow for the roof angle calculator.

For example if you find 4 inches of height with the tape measure at the 12 inch mark on the level your slope is 4 12 or 4 in 12. The 7 means that the roof rises 7 for every 12 it runs. Example a the measurements are taken from on top of the roof. To accurately calculate the area of your roof you must first determine its slope or pitch.

Finally enter the value of the rafter length and. How to calculate roof pitch. The slope of your roof is the ratio of vertical distance rise to horizontal distance run. Degrees to pitch rise in run determine the area of the roof s footprint which is the area covered by the roof regardless of slope or the apparent area of the roof when you look straight down at it like from a satellite.

There s no need to simplify them. A ratio is the most common way of expressing roof pitch or roof slope but degrees are also possible. Just write down the measurements you found. Then enter the value of the run and choose the unit of measurement from the drop down menu.

To do this you will need to write down the measurements that you have taken from the rafters. The example to right shows 2 different ways to determine or calculate roof pitch also called roof slope. Rafter rise run from the pythagorean theorem. A roof s pitch is determined by how much it rises vertically for every foot it runs horizontally.

For example when a roof has a slope of 5 12 the roof is 5 inches high for every 12 inches long. Pitch tan angle where angle is the roof pitch expressed in degrees.