How to Measure for a Metal Roof Installation

Installing a metal roof is a significant investment in your property’s longevity and energy efficiency. However, to ensure a successful installation, accurate measurements are paramount. In this guide, we’ll walk you through a step-by-step process on how to measure for a metal roof, ensuring a perfect fit and a durable, weather-resistant roof.

1. Gather Your Tools

Before you begin measuring, make sure you have the necessary tools at hand:

  • Tape Measure: A reliable, retractable tape measure with both metric and imperial units is essential.


  • Pencil and Notepad: You’ll need these for recording measurements and making notes.


  • Calculator: For accurate calculations, especially when dealing with complex roof structures.


  • Ladder and Safety Gear: Ensure you have a sturdy ladder and necessary safety gear to access and work on the roof safely.

2. Identify the Roof Type

Understanding your roof’s type is crucial for accurate measurements. The two primary roof types are:

  • Gable Roof: This is the most common type, characterized by two sloping sides that meet at a ridge in the middle.


  • Hip Roof: A hip roof has slopes on all sides, making it more complex to measure.

Identify your roof type to plan your measurements accordingly.

3. Measure Roof Dimensions

Start by measuring the roof’s dimensions. For a gable roof:

  • Step 1: Ridge Length: Measure the length of the ridge, which is the highest point where both sides of the roof meet. Measure from end to end.


  • Step 2: Eave Length: Measure the length of the eaves, which is the horizontal overhang at the bottom of the roof. Measure along both sides.


  • Step 3: Roof Slope: Measure the slope height by extending your tape measure from the eave to the ridge, perpendicular to the roof’s surface. Repeat on both sides.

For a hip roof:

  • Step 1: Ridge Length: Measure the length of each ridge on all sides.


  • Step 2: Eave Length: Measure the length of the eaves on all sides.


  • Step 3: Roof Slope: Measure the slope height on all sides.

4. Determine Roof Pitch

Knowing the roof’s pitch (slope) is crucial for ordering the correct amount of metal roofing material. The pitch is typically expressed as a ratio, such as 4:12 or 6:12, indicating the rise in inches for every 12 inches of horizontal run.

To measure the pitch:

  • Step 1: Place your ladder securely to access the roof.


  • Step 2: Position the level horizontally on the roof’s surface.


  • Step 3: Measure the vertical distance from the level to the roof’s surface (rise).


  • Step 4: Divide the rise by 12 (horizontal run) to calculate the pitch ratio.

5. Account for Roof Features

Metal roofing should be measured around any roof features like chimneys, vents, skylights, and dormers. Measure the dimensions of these features, their distances from the roof edges, and their positions on the roof.

6. Calculate Material Requirements

With all your measurements in hand, calculate the amount of metal roofing material required. Here’s a basic formula:

  • Roof Area = Roof Length x Roof Width

For gable roofs, you only need to measure one side and multiply by two. For hip roofs, you’ll need to measure each side separately.

Remember to account for waste due to cutting and any additional roofing material required for overhangs, flashing, and trim.

7. Consult a Professional

Measuring for a metal roof can be complex, especially if your roof has intricate features or irregular shapes. In such cases, consulting with a professional roofing contractor is advisable. They have the experience and expertise to provide accurate measurements and recommendations for your specific roof.

8. Double-Check Your Measurements

Before placing your order or starting the installation, double-check all your measurements. A small error in measurement can lead to costly mistakes in material ordering and installation.

Conclusion: Measure Twice, Roof Once

Accurate measurements are the foundation of a successful metal roof installation. By following these step-by-step instructions, you’ll ensure that you have the precise measurements needed to order the correct amount of roofing material and complete the installation smoothly. A well-measured metal roof not only enhances your property’s durability but also adds to its aesthetic appeal and energy efficiency.