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Construction & DIYGenerated accuracy model review: 2026-05-06
AC Size (BTU) accuracy and testing
This page documents how Calwarden builds trust for this calculator: source notes, regression-style default tests, limitations, assumptions, unit handling, rounding, and visible change history.
Formula source
- The base calculation assumes ~20 BTU per square foot for a standard room with 8ft ceilings. * **Sunny Room:** Adds 10% to the requirement. * **Shaded Room:** Subtracts 10% from the requirement. * **Kitchen:** Typically adds 4,000 BTU (heat from appliances).
Test cases
Default input regression check
Generated from the checked-in default inputs and calculate function.
Inputs
- Room Area: 400 ft²
- Sun Exposure: Normal
Expected outputs
- Recommended BTU: 8,000 BTU
Known limitations
- This page documents the checked-in calculator logic and does not certify results for every real-world edge case.
- Use the result as a planning estimate unless the calculator page states a stricter purpose.
Assumptions
- The rule of thumb assumes a standard residential room with typical 8-foot ceilings.
- The calculator adjusts only for room area and sunlight, not occupancy, kitchens, or poor insulation.
- Room area must be greater than zero for the estimate to be meaningful.
Unit handling
- Room Area accepts values in ft².
- Sun Exposure accepts one of the configured options.
- Recommended BTU is displayed in BTU.
Rounding rules
- Number displays use up to 2 decimal places in the calculator UI.
Version history
1.0.0 - 2026-05-06
Generated accuracy and testing page from the current ac-btu-calculator calculator definition.
Change log
2026-05-06
Published default regression test documentation and metadata fallbacks for AC Size (BTU).
Calculator transparency
Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.