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Energy Estimator
Preliminary load & compliance screening for Florida residential projects, modeled on the FBC 2023 (8th Ed.) R405 Simulated Performance Alternative and ACCA Manual J principles.
Instructions & code basis ▼
How to use this tool:
- Enter project data. The form is pre-filled with typical Florida values. Hints below each field explain what’s expected.
- Calculate. The report shows a preliminary EPL compliance score, a Manual S-style HVAC sizing check, annual energy breakdown, and peak load summary.
- Save, load, or print. Save inputs to a JSON file, reload a saved project later, or print a clean PDF report that documents every input and assumption.
Code basis: simplified algebraic models based on the principles of FBC 2023 Energy Conservation §R405 (Simulated Performance Alternative), 2021 IECC prescriptive baselines (Table R402.1.3, including the mass-wall path for CBS construction), and ACCA Manual J peak-load methodology. Baseline HVAC equipment is set at the current federal minimums (SEER2 14.3 / HSPF2 7.5). Intended for preliminary estimation only.
Preliminary Compliance Report
Annual energy (kWh/yr)
| Component | Proposed | Baseline | Δ |
|---|
Peak cooling load (Btuh)
| Load component | Proposed | Baseline |
|---|
Peak heating load (Btuh)
| Load component | Proposed | Baseline |
|---|
Inputs & assumptions of record
⚠ Legal disclaimer
This tool is provided for informational and preliminary design purposes only. It does not constitute official energy code compliance documentation under the Florida Building Code (FBC) or any Authority Having Jurisdiction (AHJ). This calculator simulates aspects of the R405 Simulated Performance Method and basic Manual J load calculations using simplified public-domain methods and conservative default values.
It is not a substitute for:
- EnergyGauge-certified simulations
- HERS Rater or PE-signed energy reports
- Manual S equipment selection
- Required blower door or duct leakage test results
Users assume all liability for interpretation, submission, or construction based on this tool.
Oasis Energy Estimator v2.0 · MIT License · windcalculations.com
Questions or need a stamped version? Email us at info@oasisengineering.com
This tool is provided for educational and preliminary design purposes only. Use of this calculator does not constitute code compliance or professional engineering certification. Users assume full responsibility for interpreting and applying the results.
Built with ❤️ by Oasis Engineering · View on GitHub
