Window Energy Calculator

Calculate the energy loss and potential savings from upgrading your windows. Compare single, double, and triple pane options and see payback period.

Number of Windows

Avg Window Size (sq ft)

Current Window Type

Upgrade To

Annual HVAC Cost ($)

Total Window Area

180 sq ft

Annual Savings

$436/yr

Estimated Install Cost

$4,800

Payback Period

11.0 years

U-value improvement: 1.1 → 0.3 (73% reduction in window heat loss). Windows account for ~30% of heating/cooling costs.

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