RED Calc Free

v1.0, Legacy Tool

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Free Tool Summary: Calculate up to eight air leakage metrics, including ACH50, equivalent leakage area (EqLA), effective leakage area (ELA), specific leakage area (SLA), and more. Determine if your building complies with the International Energy Conservation Code or Energy Star Qualified Homes requirements for ACH50 or the Washington State requirement for SLA. See Tool GuideClick 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.