How Do You Determine Roof Slope

The top of the ridge beam m y.

How do you determine roof slope.

In the united states a run of 12 inches 1 foot is used and pitch is measured as the rise of the roof over 12 inches. This will allow your project to carry the depth and detail in the roof that you wanted as well as make sure that it will maintain a sturdy and effective nature throughout. Let s assume it is equal to 6 m. Roof pitch or slope is a measure of vertical rise to horizontal run expressed in inches per foot.

Pitch is thus the ratio of the rise in inches to a 12 inch run and is often expressed using a semicolon for example 6 12. The most precise way to find the roof s slope is by measuring it from the underside. Even if you want to use a flat roof pitch calculator system you will be able to find one. Calculate the roof slope.

To measure the roof pitch you ll need an 18 or 24 inch level a tape measure and a pencil. Access one of the rafters then take the measurement this way. Write the roof slope as the ratio of rise over run or vertical distance over horizontal distance. A a roof with a 6 rise for every 12 run has a 6 per foot or 6 in 12 pitch.

Then in the attic place the end of the level against the bottom of a roof rafter and hold it perfectly level. Locate the level s 12 inch mark. For instance a 7 12 roof pitch means that the roof rises 7 inches for every 12 horizontal inches. How roof pitch is calculated to accurately calculate the area of your roof you must first determine its slope or pitch.

If you want to know how to find the pitch of a roof then start with a calculator. Thus a moderate 6 in 12 roof pitch means that the roof rises 6 inches vertically for every 12 horizontal inches it runs. Outside of the u s a degree angle is typically used. To determine the finished height of the ridge beam add the rise m and the y height.

It is often compared to slope but is not exactly the same. Use a level against the underside of the rafter you re measuring to get the most accurate value. To determine the y height measure from the bird s mouth up the calculated slope x in 12 to the top of the rafter. First measure 12 inches from one end of the level and make a mark.

For example if your tape measure found a 6 inch vertical distance to the 12 inch mark on your level the slope is 6 12 or 6 in 12. Here s an easy safe way to determine the pitch from inside your attic. Measure the rise of your roof.