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Home & UtilitiesGenerated accuracy model review: 2026-05-06
Insulation Savings Calculator 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
- Annual savings = annual heating/cooling cost x savings percent. Payback = net project cost / annual savings.
Test cases
Default input regression check
Generated from the checked-in default inputs and calculate function.
Inputs
- Annual Heating/Cooling Cost: 2,400 $/yr
- Expected Reduction: 12%
- Project Cost: $4,500
- Incentives/Rebates: $500
Expected outputs
- Estimated Annual Savings: $288.00
- Net Project Cost: $4,000.00
- Simple Payback: 13.89 years
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
- All prices, rates, taxes, and usage values are entered by the user.
- Calculations run locally in your browser and are not stored by Calwarden.
- This is planning math, not financial, tax, engineering, or legal advice.
Unit handling
- Annual Heating/Cooling Cost accepts values in $/yr.
- Expected Reduction accepts values in %.
- Project Cost accepts values in $.
- Incentives/Rebates accepts values in $.
- Estimated Annual Savings is displayed as currency.
- Net Project Cost is displayed as currency.
- Simple Payback is displayed in years.
Rounding rules
- Number displays use up to 2 decimal places in the calculator UI.
- Currency outputs are displayed with standard US dollar formatting.
- Input precision follows configured step values where provided.
Version history
1.0.0 - 2026-05-06
Generated accuracy and testing page from the current insulation-savings-calculator calculator definition.
Change log
2026-05-06
Published default regression test documentation and metadata fallbacks for Insulation Savings Calculator.
Calculator transparency
Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.