Typical U-factor & SHGC by frame material and glazing

Typical published planning values / code minimums — NOT a certified design or a compliance sign-off. Actual egress compliance and energy performance depend on your local building code (AHJ), climate zone, the exact product’s NFRC-rated U-factor & SHGC and the installation; confirm against local code and the manufacturer’s NFRC label, and consult a pro. Structural headers for enlarged openings, whole-building heat-load / HVAC sizing and code certification are set by code and a professional — not engineered here.

This companion table gives the LABELED typical whole-window U-factor and SHGC by frame material and glazing — from a bare aluminum single pane to a triple-pane low-E with argon/krypton — and derives the whole-window R-value from the reciprocal identity R = 1 ÷ U. Use the product’s NFRC label for the real numbers; these are planning typicals. It backs the single vs double vs triple pane compare and the low-E / gas-fill reference.

Typical whole-window U-factor by frame material and glazingAluminum, single pane (no thermal break)U 1.20Wood/vinyl, single paneU 0.90Aluminum, double paneU 0.65Vinyl/wood, double pane (air)U 0.48Vinyl/wood, double pane low-E + argonU 0.30Fiberglass/composite, double low-E + argonU 0.28Vinyl/fiberglass, triple low-E + argon/kryptonU 0.18← lower U-factor = less heat loss
Frame × glazingTypical U-factorTypical SHGCR-value (1 ÷ U)
Aluminum, single pane (no thermal break)1.200.700.83
Wood/vinyl, single pane0.900.651.11
Aluminum, double pane0.650.551.54
Vinyl/wood, double pane (air)0.480.552.08
Vinyl/wood, double pane low-E + argon0.300.273.33
Fiberglass/composite, double low-E + argon0.280.253.57
Vinyl/fiberglass, triple low-E + argon/krypton0.180.205.56

LABELED typical planning values — use the product’s NFRC label for the real numbers. Whole-window R-value is derived from R = 1 ÷ U-factor and is far below a wall’s cavity R-value (the wall and the window are rated separately). Snapshot: 2026-07-11.