4 On 12 Roof Pitch

Image 1 12 to 12 12 roof pitch 7 12 pitch.

4 on 12 roof pitch. Most roof s have a pitch in the 4 12 to 9 12 range. Roof pitch and corresponding angles. If the rise is 6 inches for every 12 inches of run then the roof slope is 6 in 12 the slope can be expressed numerically as a ratio. A pitch over 9 12 is considered a steep slope roof between 2 12 and 4 12 is considered a low slope roof and less than 2 12 is considered a flat roof.

If this isn t practical then perform the same measurement on the underside of the roof. Places that use metric measurement systems use a degree angle or. Roof pitch degree table. A 4 12 is a roof slope that rises by 4 inches for every 12 inches across.

A 4 12 roof pitch indicates the roof rises 4 inches in height for every 12 inches as measured horizontally from the edge of the roof to the centerline. These trusses the meet building code criteria as specified by structural building components of america sbca and the truss plate institute tpi. In the usa the rise is rationalized to a ratio of so many measuring units rise to each 12 measuring units of run e g 3 12 4 12 5 12. The slope ratio represents a certain amount of vertical rise for every 12 inches of horizontal run.

The table below shows common roof pitches and the equivalent grade degrees and radians for each. This means if a roof rises 4 in the length of 12 your roof pitch would be 4 12 or 18 43 degrees. For example if the peak of your roofline is 18 feet from the outer wall where it starts and the wall as a 4 by 12 pitch then that means that the roof would be 6 feet in height above where it started at the wall. On blue prints architects engineers usually display the pitch of a roof in the format shown on the image where number 4 represents a rise and number 12 represents a length.

The gentle slope of a 4 12 pitch roof falls. A roof that rises 4 inches for every 1 foot or 12 inches of run is said to have a 4 in 12 slope. This forms an angle of 18 5 between the horizontal section and the roof and creates a gentle incline that is seen as a midpoint between a low pitch and medium pitch roof. The 4 12 pitch is a roof that rises vertically toward the peak 4 inches for every 12 inches of horizontal run.

We included a roof pitch chart below the 7 12 example image and the calculator below that. In the imperial measurement systems pitch is usually expressed with the rise first and run second in the usa run is held to number 12.