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Introduction to Manual J load calculations and why they are important

Overview of Manual J

Manual J is designed to be used for residential buildings only that have three or fewer above-grade stories

Can I use Manual J for commercial buildings?

How to set infiltration load calculations with the tightness or blower door method

How to model air infiltration

How to model losses and gains for ductwork in unconditioned space

How do I model ducts?

Use a flash light, lighter or laser to quickly verify glass type

How to determine if you have "low-e" or "clear" windows

How design conditions are set automatically and how they can be adjusted per local code requirements

What are design conditions and how can I change them?

Learn how we set starting assumptions using the year built and location of a home

Smart starting assumptions for insulation, windows and air leakage

Background on how CFMs are calculated and how they should (and should not) be used

Approximate airflow CFMs for cooling or heating

Eric Fitz

Manual J background and how to fine tune your designs

Manual J and Load Calculations

Find answers and get help from Intercom Support and Community Experts

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