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      How to Use the Ice and Water Shield Calculator

      A step-by-step guide to using the Ice and Water Shield Calculator in your building code reports.

      The Ice and Water Shield Calculator helps you determine the necessary Ice and Water Shield (IWS) membrane for various rounding use cases (e.g., half roll, full roll) on all roofing projects. 

      Step 1: Access the Calculator

      On your building code report, select the Ice and Water Shield Calculator.

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      Step 2: Enter All Required Inputs

        • Roof size
          To get the roof size, use the total roof area, also known as the removal SQs as provided in a roof measurement report. If calculated in Square Feet (SF), divide by 100 to convert to SQs.
        • Predominant pitch
          Use the predominant pitch of the roof. Most measurement providers include this in the roof report.
        • Eave Length
          Use the total eave length measured or provided in a roof measurement report. You can also calculate IWS for each facet of the roof by using the eave width listed for the facet.
        • Valley Length
          Use the total eave length measured or provided in a roof measurement report. You can also calculate IWS for each facet of the roof by using the eave width listed for the facet.
        • Soffit Depth
          Also known as soffit overhang. Measure from the street-facing side of the fascia to the exterior wall.
        • Inside Interior Wall
          The distance inside the interior of the house used to calculate the amount of Ice and Water Shield (IWS) material needed for the roof. According to IRC, this is typically 24 inches from the interior wall.
        • Stud size
          Select the appropriate stud size 
          • 2x4 for residential properties
          • 2x6 for commercial properties
        • Exterior Type
          Choose the exterior type of the property: 
          1. Brick
          2. Siding
          3. Stucco
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        Step 3: Calculate the Roof Estimate

        Click Calculate to generate your roof estimate. 02

        Step 4: Create a Report 

        Click Create Report to download the full PDF of the roof estimate. You can print or share this report. 03

      Tip: Once you have calculated the ice and water shield estimate, click View Note for a detailed breakdown of your roofing waste estimate. Click Copy Note to copy the calculations of the Ice & Water Shield Calculator.

      • The PDF report for the Ice & Water Shield Calculator should look like this: 
        IWS-4

      Additional Resources

      Contact Support

      If you need further assistance, please contact our support team at code@oneclickcode.com or visit our Support Page.