What Is A Roof Pitch? Beginners Guide For Homeowners | Roof Troopers
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What Is A Roof Pitch? Beginners Guide for Homeowners

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Posted By: Roof Troopers

roof pitch of residential brick home

If you own a home, there’s no doubt that you’ve heard the term “roof pitch” thrown around before, but do you know what it is? What is a roof pitch? For many homeowners, a roof pitch can be mysterious and intimidating.

But don’t worry – in this blog post; we’ll explain roof pitch: what it is, why it matters for your home, and how to determine whether or not your current roof has an appropriate one.

Whether you’re considering renovating your existing roof or building an entirely new structure, this post will provide valuable information so that you can ensure that the work is done.

What is a Roof Pitch?

roof troopers use tool to measure roof pitch

Roof pitch is integral to any roof and should be calculated before building. Roof installation can get particularly challenging if the steepness isn’t calculated accurately, so it’s essential to understand what roof pitches are and how they work. As defined by builders, a roof pitch “is the slope or angle of a roof, expressed as a ratio of its rise to its span.”

To express this another way, a 20-degree roof pitch means that for every foot of horizontal run, there is a rise of four inches in the structure.

A flat roof communicates that its job is to provide shelter from the elements, but roofs serve more than one purpose when angles come into play. They are also aesthetically pleasing and help water runoff during storms.

Some common residential grades for roofs include 6/12 (6 inches up for every 12 inches forward), 4/12 (4 inches up for every 12 inches forward), 8/12 (8 inches up for every 12 inches forward), and even 16/12 (16 inches up for every 12 inches forward).

It’s, therefore, essential to accurately measure and calculate the right kind of roof pitch that your structure requires before starting any construction work.

Common Types of Roof Pitch

The most common roof pitches are as follows:

High-Pitched Roofs

High-pitched roofs are the most common type of roof pitch today. These roofs have a steep slope, usually 412 to 1212 (or 25% to 45%).

High-pitch roofs provide better drainage and ventilation than low-pitch roofs. They also tend to be more aesthetically pleasing since they can make a home look taller and more majestic.

However, high-pitch roofs require more maintenance due to their steeper slopes and increased exposure to the elements.

Low-Pitched Roofs

close up of low roof pitch with tarp after leak

Low-pitched roofs were popular in the 1960s but are not as commonly used today due to their lack of drainage capabilities compared with higher-pitched options. Low-pitched roof pitches typically range from 112 to 412 (or 8% up to 25%).

Low-pitch roofing is ideal for areas that experience minimal rainfall or snowfall because it provides less protection against water damage caused by heavy precipitation or extreme weather conditions such as hail storms or hurricanes.

It’s essential for homeowners who choose this option to ensure that their gutters are adequately maintained so that any water runoff is directed away from the foundation of the house rather than pooling around it, which could lead to structural damage over time.

Flat Roofs

Flat roof designs appear altogether level but have a slight pitch – usually 14 inches per foot – designed into them for drainage purposes.

Flat rooftops may be found on commercial buildings, garages, sheds, porches, and some residential homes, depending on local building codes and regulations in your area.

While flat rooftops offer an attractive modern look when done correctly, they do require regular maintenance, such as cleaning out gutters regularly and inspecting seams.

How to Calculate Roof Pitch From a Ratio

Calculating roof pitch from a ratio isn’t as difficult as it may seem. First, however, you must follow the steps to get an accurate reading.

  • To begin, you must measure the length of your roof – this is the horizontal distance from the edge of your roof to the peak.
  • Subsequently, it would be best to determine the elevation – the vertical distance between your roof’s edge and peak. Once you have these numbers, divide the rise by the run to get your ratio.
  • The next move is to figure out the tangent of this ratio. To do this, divide one by your tangent result.
  • To complete the process, multiply your outcome by 180/π, and you’ll have accurately determined your roof pitch!

Following these steps, you can easily calculate your home’s roof pitch.


Are you still curious about a roof pitch? Keep reading to find out the answers to some of the most commonly asked questions.

What does a 4/12 roof pitch mean?

A 4/12 roof pitch means the roof rises four inches for every 12 inches horizontal run. This is a famous slope used in residential construction as it provides good drainage and is relatively easy to construct. The steepness of this pitch also helps shed snow and rainwater quickly off the roof, making it an excellent choice for areas with heavy precipitation.

What does a 9/12 roof pitch mean?

A 9/12 roof pitch means the roof rises nine inches for every 12 inches horizontal run. This steep slope is commonly used on homes with two stories or more, allowing for increased headroom in the upper levels.

The steep roof helps to provide better drainage and protection from snow and rain. In addition, a steeper incline can simplify the job of laying shingles, leading to lower labor costs when setting up a new roof.

How do I determine my roof pitch?

man getting on the roof to measure roof pitch

To calculate your roof’s steep pitch, you must measure the vertical elevation over a 12-inch span from the roof’s peak to where it intersects with a wall or fascia board. Then, measure from the roof’s edge (at its highest point) down to where it meets the wall or fascia board. 

Divide this number by 12 and then multiply it by 12 again – this is your roof’s pitch expressed as a ratio. For example, if your measurement was 6 inches, the pitch of your roof is 6/12.


A steeply-pitched roof may be more aesthetically pleasing, but a low-pitched one can also work well in certain climates. If you’re unsure which type of pitch to choose for your home or need help with any repair job on an existing structure, Roof Troopers are here for you.We provide professional services to ensure all roof-related aspects are taken care of properly so that homeowners don’t have to worry about any potential damages caused by weather or time. So contact us today and let us know how we can help!


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