RED Calc Free

v1.0, Legacy Tool

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Free Tool Summary: Allows you to easily achieve accurate Zone Pressure Diagnostics (ZPD) testing results. Determine air leakage between the house and zone, zone and outdoors, and through the zone. Displays uncertainty as an absolute amount and percentage. See Tool Guide. Click on any input or result label for help. By using this tool (application) you agree to the Terms of Use.

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This legacy tool is NOT optimized for mobile devices. Stay tuned for the mobile-optimized version.