RED Calc Free

v1.0, Legacy Tool

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You can use RED Calc Pro for 30 days free!

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Free Tool Summary: Calculates required minimum flow rate of dwelling-unit ventilation. Complies with ASHRAE 62.2-2010, including Alternative Compliance Path and fan run-time. Scope includes detached dwellings and dwelling units in multifamily buildings of three stories or fewer above grade. See Tool Guide. Click on any input or result label for help. By using this tool (application) you agree to the Terms of Use.

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