Flat Roof Pitch Angle

The table below shows common roof pitches and the equivalent grade degrees and radians for each.

Flat roof pitch angle.

A 12 12 pitch roof has a pitch angle of 45. How roof pitch determines suitable roofing systems. The roof pitch angle greatly factors into the replacement cost of the roof. Roofs having a lower pitch have a greater chance of creating water leaks as well as ice damming and so they require an intensive waterproofing system.

This means that the rise of the slope goes up or down 8 inches for every 12 inches. Asphalt shingles are appropriate on roofs with conventional pitches between 4 12 and 9 12. The slope of a roof or pitch is determined by how many inches the roof rises over 1 foot or 12 inches. In order to achieve this drop a slightly steeper angle of 1 40 1 44 should be the aim when installing a flat roof as this accounts for surface.

What degree angle is a 12 12 pitch roof. To convert between american roofing ratios and pitch degrees follow these steps. Roof pitch refers to the measurement of the slope of a roof and you express this as a ratio. The combination of two numbers are used to display or show the roof pitch.

To put it in perspective the angle of this slope would be around 30 degrees. A steep roof usually sheds water quickly which is quite difficult to work on. This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement. An example for a steep sloped roof is 8 12.

Roof pitch is a term describing how steep or flat your roof slope is. 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. Normally 1 80 0 72 is the recommended minimum angle for a slope and this is universal across the vast majority of flat roofing systems regardless of the materials that they incorporate. Low slope or flat roofs should not be roofed with asphalt shingles because it is much easier for water to infiltrate the roofing material on a roof with a shallow pitch.

Two most common methods 4 12 or 4 12 are used for marking the pitch of a roof. Divide the first part of the ratio by 12 to work out the pitch. Although there s isn t any standard pitch of a roof used on all kinds of sloped roofs you can determine the range of pitches by using a roof angle calculator and by considering factors like the local climate and roofing materials. Roof pitch angle and slope factor charts.