NFRC Label

The NFRC label is the standardized energy performance sticker that appears on all windows certified by the National Fenestration Rating Council (NFRC). The NFRC is a non-profit organization that establishes uniform procedures for testing and certifying the thermal and optical performance of windows, doors, and skylights. The label allows consumers to make apples-to-apples comparisons between different window products and verify Energy Star compliance.

What the NFRC Label Shows

• U-Factor — heat loss rating; 0.20–1.20 typical range; lower is better; Energy Star requires ≤ 0.27 for North-Central (Ohio)
• Solar Heat Gain Coefficient (SHGC) — solar heat admission; 0–1; lower blocks more solar heat; Energy Star requires ≤ 0.40 for Ohio
• Visible Transmittance (VT) — fraction of visible light admitted; 0–1; higher means more daylight
• Air Leakage (AL) — cfm/ft²; lower is better; ≤ 0.30 typical; ≤ 0.10 for high-performance windows
• Condensation Resistance (CR) — 0–100 scale; higher means the window surface stays warmer and resists condensation

How to Use the NFRC Label

When shopping for replacement windows in Ohio:

1. Check U-factor ≤ 0.27 for Energy Star compliance
2. Check SHGC ≤ 0.40 for Energy Star compliance
3. For south-facing windows in a well-insulated home, consider SHGC 0.35–0.50 to capture passive solar heat in winter
4. Verify VT ≥ 0.50 to maintain comfortable daylighting
5. For noisy locations, note that the NFRC label doesn’t show STC — ask for the manufacturer’s acoustic data separately

NFRC vs. Energy Star

NFRC certification is the testing and labeling program. Energy Star is a separate program (run by the EPA) that uses NFRC ratings to set minimum performance thresholds by climate zone. A window must be NFRC-certified before it can be Energy Star qualified. Both logos may appear on the same window.