Beta

The free tools here work and are honest about their limits, but the calculation engine has not yet been checked against another tool on a real house.

The calculation engine has not yet been checked against a reference tool on a real house. Treat every number here as a starting point to verify, not a finished answer.

Check the results before you act on them. Verify against the equipment data plate, the manufacturer's installation manual, and your own measurements. You are responsible for what you install — Cheek Heating & Cooling LLC is not liable for decisions made from this tool's output.

Built by working HVAC contractors

Free ACCA Manual J 8 Abridged Edition load calculator + equipment sizing report

Generate residential heating and cooling load calculations using the ACCA Manual J 8 Abridged Edition (MJ8ae) method. Get a customer-ready PDF report you can use to size HVAC equipment and justify proposals — free, no signup required.

Start a free calculation Full workspace (save projects)

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Whole-house load calc

Block-load heating + cooling using the ACCA Manual J 8 Abridged Edition method. ACCA design temps for your jurisdiction, per-orientation glazing solar gain, infiltration model, internal gains. Real BTU/h numbers, not rule-of-thumb.

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Equipment recommendations

ACCA Manual S method — the smallest standard size that meets the load, no oversizing. Furnace input + AC tonnage + heat-pump alternative. A generic standard-capacity estimate, not a full Manual S selection against a manufacturer's expanded performance data. Incentives are not tracked — the report tells you to check current federal, state and utility programs yourself.

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Customer-ready PDF

Professional report with project info, design conditions, load breakdown, equipment tiers, and a methodology section. Drop straight into your proposal package.

Honest about what this is. HVAC Design Studio implements the ACCA Manual J 8 Abridged Edition (MJ8ae) calculation method — same procedural shape as the Johnstone Supply MJ8ae spreadsheet used in HVAC trade training. It is not an ACCA-certified Manual J 8 product (that's a separate paid certification program). For permit submissions in code-strict jurisdictions, cross-check against an ACCA-approved tool. For commercial work that requires sealed mechanical drawings, pair with a licensed Professional Engineer.

Why we built this

Cheek Heating & Cooling LLC (Muncie, IN) was tired of paying per-report on the legacy tools and watching small-shop contractors skip load calcs entirely because the software was expensive or hard to learn. HVAC Design Studio is the contractor-built alternative: free for the load calc and PDF, focused on the workflow real HVAC techs actually run, and designed to scale into the deeper engineering tooling we use ourselves.