The Minimum Pitch Needed for a Metal Roof (Professional Advice)

6 minutes Read

Level Edge Construction

When it’s time for a new roof, you have plenty of options to choose from regarding the materials. Some of these options are more aesthetically appealing, while others are more economically appealing; however, it’s the pitch of your roof that will determine which roofing materials you’ll be able to use.

This is especially true for metal roofs. Standing seam panels is a top choice for modern homes for several reasons, including:

• Aesthetics
• Durability
• Longevity
• Affordability

Of course, you’ll need to make sure that your roof pitch meets the minimum pitch for metal roof requirements. 

In this article, we’ll cover everything you need to know about roof pitch when it comes to metal materials — including how to do the calculations on your own.

What Exactly Is Roof Pitch?

Whenever you hear the terms pitch, angle, incline, or roof slope in this context, it’s in reference to the steepness of your roof. While the terms are interchangeable, the roof pitch is always expressed as “12 inches.”

In the simplest terms, the pitch of a roof is determined by how many inches the incline rises for every 12 inches that it runs horizontally. More specifically, roof pitch estimates are comprised of ratios and denoted with a slash or colon. Additionally, the first number in the ratio is the numerator. It represents the vertical height measurement of the roof in increments of the second number — the denominator — which is the horizontal height measurement. 

For example, if your roof increases in height by four inches for every 12 inches (or foot) of horizontal run, then it’s considered to have a “4 pitch” or a “4-in-12-pitch” which would be denoted as “4/12” or “4:12.”

It should be noted that despite there being math here, the horizontal portion of the pitch remains a constant 12 inches. There’s no fraction reduction. Although, there may be some multiplication required if you’re doing the calculations yourself. (We’ll get to that later).

Why the Incline of Your Metal Roof Matters

Generally speaking, roof pitch is important for several reasons:

• It allows you or your contractor to estimate the amount of material needed for the job.
• It’s a deciding factor in style and aesthetics.
• It can help determine the longevity of your roof concerning durability.
• It also helps determine how long it will take for debris and water to run off the roof.

When it comes to metal roofs, too low of a pitch could cause issues with air and water movement through the roof sheathing, which can give way to condensation buildup. While metal roofs are considered to be virtually impermeable, as they’re known to be resistant to the elements, corrosion, shrinkage, and cracks, the wrong roof pitch would render them incredibly vulnerable to all of those things. 

Too much condensation building up underneath your metal roofing panels won’t just damage the roof itself but also any wiring, wood, or metals beneath it. This is why any roofs you see with a low pitch — metal or otherwise — are accompanied by coverings. 

How to Calculate Roof Pitch

If you’re looking to get an idea of what you’re in for when it comes to metal roofing materials, you can easily calculate the pitch of your roof on your own. 

Of course, the first thing you want to do is make sure you have safe access to your roof. The next thing you’ll need to do is to make sure that you have a level that’s at least 24 inches long (like a contractor’s level) and a tape measure.

To get started, place the short end of the level against the edge of your roof, balancing it as it extends upward into the air until it becomes level. From there, you can measure down from the exposed short end back to the roof’s surface with the tape measure.

Take your results and divide them by 12 inches using the segments on your level. For example, if you’re using the contractor’s level and get a measurement of 12 inches, then your roof’s pitch is 6:12.

If you don’t have the proper tools, there is a way to “guesstimate” the pitch of your roof. The exposed face of roof clapboards (which is about four inches) and a dollar bill (which is six inches) can be used as your “tools.” So, you can just count the clapboards from the low end of your roof to its peak and then use a dollar bill to figure out the horizontal stride and make your calculations from there.

What Is the Minimum Pitch for Metal Roofs?

The rule of thumb with metal roofs is that they should be worth their weight in value. You also want to ensure they don’t end up with a bunch of different issues due to improper roof pitch. 

That’s why the recommended minimum pitch for metal roof applications is 3 ½:12 (three and a half of 12). Some metal roofing manufacturers say that 1.4:12 is acceptable; however, it comes down to the overall geometry of your house.

It also comes down to what your professional metal roofing contractor recommends. They’re the only people who can accurately determine the pitch you need as well as the right coverings to ensure that your metal roof remains strong and durable for years to come. 

Need Help With Your Roof Pitch?

Knowing the minimum pitch for a metal roof is only half the battle. You also want to be certain that the measurements taken will be accurate and that the new roof is installed properly. 

That’s where we come in. At Level Edge Construction, our experienced contractors can take care of all your roofing needs from beginning to end, including taking the time to educate you on how to care for your new roof and much more. Get in touch with us today to talk about your roofing options or to ask about our other services. 

We also offer free home inspections!

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Level Edge Construction