What is a 9 on 12 roof pitch | 9/12 roof pitch

A 9 on 12 roof pitch, often written as 9/12 or 9:12, indicates the slope of a roof. It means that for every 12 inches (or 1 foot) of horizontal distance, the roof rises 9 inches vertically. In other words, the roof angle is such that it has a 9/12 pitch. This is a relatively steep pitch and is commonly found on steeper-sloped roofs, which can shed rain and snow more effectively.

Pitch of roof is the measurement of roof’s slope expressed in ratio, fraction, percentage and in degrees, there is no one single standard for pitch of the roof used on all sloped roofs, determining factors such as roofing material and local climate condition help to determining the appropriate range of the pitch for a given building or structure. But the 9/12 roof pitch is the most common residential roof pitch in which roof rafter rises 9 inch for every 12 inches or 1 foot horizontal distance or run.

9/12 roof pitch step is enough to shed water quickly and also being non comfortable for walkable. 9/12 roof pitch express in fraction, percentage, ratio or in angle.

In earlier time from the beginning of civilization peoples are always looking for house which built by timber covered with roof to prevent from heavy rainfall and snowfall conditions. Design and construction of roof is depending on many factors but one of the most common important factor is climatic and weather condition of your surrounding areas, in your cities and countries.

The area which has heavy rainfall and snowfall require good drainage for roof, roof drainage depending on slope of the roof provided, based on slope of roof it is categorised into two types flat roof and pitched roof or sloping roof. These are two types of roof structure based on slop.

Flat roof is type of roof in which slope is generally less than 10°, which only enable to ensure adequate drainage of rainwater in low to moderate rainfall regions. Pitched roof is type of roof comprising sloping surface or surface with an angle of usually over 20°, generally it slopes downward in one two or more parts depending on design and construction.

Pitch of roof lower than 4/12 have a slight angle called as low slope roof, pitches of less than 2/12 considered as flat roofs, pitches higher than 9/12 are called as steep slope roofs, pitches ranging between 4/12 to 9/12 is considered as conventional roofs pitch suitable for most of residential house. In this article we only explain about 9/12 (9 on 12, 9 over 12 or 9 in 12) roof pitch angle and their height.

9 on 12 roof pitch

The 9/12 or 9 on 12 roof pitch are most common types of residential roof pitch which are a sloping surfaces with an angle of usually 36.82° degrees steepness of a roof with it’s vertical rise of 9 inches over its 12″ or 1 foot horizontal distance or run in building construction. These are most protective and efficient solution in wet and cold weathers.

9 on 12 roof pitch
9 on 12 roof pitch

The 9/12 roof pitch is the most common residential roof pitch. it is step enough to shed water quickly and also being non comfortable for walkable. 9/12 roof pitch express in fraction, percentage, ratio or in angle.

Roof pitch, or slope, is a measure of vertical rise to horizontal distance or run expressed in inches per foot. A roof with a 9″ rise for every 12″ run has a 9″ per foot.

In simple word 9 on 12 or 9/12 roof pitch is slop created by the rafter it can be calculated as the angle rafter makes with the horizontal or the ratio between the vertical Rise and horizontal run of roof. It can be expressed in ratio between rise and run in the form of 9:12, a pitch of 9:12 means a roof that rises 6 inches for every 1 foot or 12 inches of run is said to have a “9 on 12” slope or 9/12 pitch for roof.

What is a 9/12 roof pitch?

9/12 or 9 on 12 roof pitch is define as roof rafter that vertical rises 9 inches for every 1 foot or 12 inches of horizontal distance or run is said to have a “9 on 12” slope, “9 in 12” slope or 9/12 roof pitch and their pitch roof angle is about 36.82°.

9/12 roof pitch angle

A roof pitch of fraction 9/12 (9 over 12, 9 on 12 or “9 in 12” slope, or in ratio 9:12) is equal to 36.82 degrees of angle. This slope is best for many residential house in cold and wet weather climatic condition.

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How how to determine angle for 9/12 roof pitch

You can determine this in two easy steps:-

1) calculate the ratio of pitch such as pitch = rise/run such as 9/12 = 0.75

2) find the inverse tangent of pitch to get the angle in degrees, such as tan inverse of pitch = tan-1(0.75) = 36.82°

Thus a roof pitch of fraction 9/12, 9 over 12, or “9 in 12” slope, or in ratio 9:12 is equal to 36.82 degrees of angle.

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9/12 roof pitch in degrees

A roof pitch of fraction 9/12 (9 over 12, 9 on 12 or “9 in 12” slope, or in ratio 9:12) is equal to 36.82 in degrees of angle. This slope is best for many residential house in cold and wet weather climatic condition.