Retrofit Glazing
VIG is the only high-performance glass thin enough to fit existing single-glazed frames — without replacing them. Historic buildings, older homes, schools, commercial properties. One glass upgrade. R12–R20 performance.
The Challenge
Most high-performance glazing is too thick for landmark buildings. Standard double-glazed IGUs start at 24mm — far too wide for original single-glazed profiles that typically accept 3–6mm glass. Building owners face an impossible choice: preserve the architecture or upgrade the performance.
VIG eliminates that tradeoff. At just 6.2mm (¼”), it drops directly into existing frames. No new mullions. No altered sightlines. No compromise on the architecture that earned the building its protection.
Original single-glazed frames accept 3–6mm glass. VIG at 6.2mm is the closest any high-performance glass has ever come to matching that profile.
Head to Head
| Metric | Standard Double-Glazed IGU | VIG |
|---|---|---|
| Profile thickness | 24 – 32mm | 6.2mm |
| Fits original single-glazed frames? | No — requires new frames | Yes — direct drop-in |
| R-value (center of glass) | R-3 to R-5 | R-12 to R-20 |
| U-value (W/m²·K) | 1.2 – 1.8 | 0.3 – 0.5 |
| Condensation | Possible (gas seal degradation) | Zero — no air in cavity |
| Sound attenuation | 28 – 32 dB | 39+ dB |
| Sightline alteration | Significant — wider mullions required | None — original profiles preserved |
| SHPO compliance | Often rejected | Compliant — preserves character |
| Historic tint options | Limited | Gray, Bronze, Green, Blue + Low-E |
| Gas fill degradation | Yes — argon leaks over time | None — vacuum is permanent |
| Tested lifespan | 20 – 25 years | 40+ years |
Why VIG Wins
No other glass technology can match VIG's combination of thin profile and high performance for historic buildings. This is the most defensible position in the glazing market.
Ideal For
Architects, building owners, facilities managers, and contractors upgrading existing glazing in:
We provide physical samples so you can evaluate VIG firsthand. Whether it’s a landmark, an older home, or a commercial building — request a sample or a quote for your project.
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