Double Glazed Window Glass | Double Glazed Insulating Glass for Windows & Doors
Double Glazed Insulating Glass Units – The Global Standard for Energy‑Efficient Windows & Doors
Double glazed window glass – also known as double glazing glass, insulated glass units (IGU), or sealed double glazing – is the most widely specified glazing product for modern windows and doors worldwide. It consists of two glass panes separated by a sealed air or gas‑filled cavity, creating a thermal barrier that dramatically reduces heat loss compared to single glazing.
For procurement managers and facade engineers, double glazed window glass is the baseline specification for virtually all new construction and renovation projects in developed markets. From residential homes to commercial office towers, double glazing is required by building codes across Europe, North America, Australia, and increasingly across Asia and the Middle East.
💡 Why double glazed glass dominates: Over 80% of new window installations in OECD countries now specify double glazing. The combination of improved thermal comfort, reduced energy bills, condensation control, and acoustic insulation makes it the minimum acceptable standard. For export‑oriented glass manufacturers, double glazed IGU represents the largest volume opportunity in the architectural glass market.
1. Quick Specification
| Item | Standard | Premium (Low‑E) |
|---|
| Configuration | 4+12Ar+4, 5+12Ar+5, 6+12Ar+6, 6+16Ar+6 | 6+12Ar+6 Low‑E, 6+16Ar+6 Low‑E |
| Overall Thickness | 20–28 mm | 24–28 mm |
| Outer Lite | 4–6 mm Tempered / Annealed | 6 mm Tempered / Annealed |
| Inner Lite | 4–6 mm Tempered / Annealed | 6 mm Tempered / Annealed |
| Coating | None (clear) | Double Silver Soft‑Coat Low‑E |
| Coating Surface | N/A | #2 (cold climate) or #3 (hot climate) |
| Cavity | 12 mm or 16 mm sealed | 12 mm or 16 mm sealed |
| Gas Fill | Air or Argon ≥90% | Argon ≥90% |
| Spacer | Aluminum / Warm Edge TPE | Warm Edge TPE / Swisspacer |
| Seal | Dual seal: PIB + Polysulfide | Dual seal: PIB + Structural Silicone |
| Desiccant | Molecular sieve ≥2800 mg/g | Molecular sieve ≥2800 mg/g |
Performance Comparison
| Parameter | Clear Double Glazing (4+12+4, Air) | Clear Double Glazing (6+16Ar+6) | Low‑E Double Glazing (6+16Ar+6) |
|---|
| U‑Value | ~2.7 W/m²K | ~2.0 W/m²K | ~1.4 W/m²K |
| SHGC | 0.55–0.65 | 0.50–0.60 | 0.25–0.35 |
| VLT | 75–82% | 72–78% | 50–65% |
| UV Blockage | ~50% | ~50% | 90–95% |
| Acoustic (Rw) | ~28 dB | ~31 dB | ~33 dB |
| Condensation Resistance | Moderate | Good | Excellent |
2. Why Double Glazed Window Glass?
2.1 Thermal Insulation
The sealed air or gas cavity between the two glass panes acts as a thermal break, reducing heat transfer through the window by up to 50% compared to single glazing. With Low‑E coating and argon gas fill, the U‑value drops to ~1.4 W/m²K – meeting the most stringent energy codes including ASHRAE 90.1, Title 24, and EPBD NZEB requirements.
2.2 Energy Cost Savings
Replacing single glazing with double glazed IGU can reduce heating and cooling energy consumption by 20–35% annually. For a typical commercial building, this translates to thousands of dollars in operational savings per year.
2.3 Condensation Control
Double glazing significantly reduces interior surface condensation because the inner pane stays closer to room temperature. This prevents mold growth, window frame damage, and occupant discomfort.
2.4 Acoustic Insulation
The combination of two glass panes and a gas cavity provides ~28–33 dB Rw acoustic insulation – a noticeable improvement over single glazing (~20–25 dB). For urban environments near traffic, airports, or railways, this is a critical specification.
2.5 Safety & Security
Both panes can be tempered or laminated for impact resistance. Even with annealed glass, the sealed unit provides a barrier that is harder to breach than single glazing.
2.6 UV Protection
Standard double glazing blocks ~50% of UV radiation. With Low‑E coating, UV blockage increases to 90–95%, protecting interior furnishings, artwork, and merchandise from fading.
3. Available Configurations
3.1 Standard Configurations
| Configuration | Cavity | Gas Fill | Typical U‑Value | Best For |
|---|
| 4+12+4 | 12 mm | Air | ~2.7 W/m²K | Budget residential, mild climates |
| 4+12Ar+4 | 12 mm | Argon | ~2.5 W/m²K | Residential, moderate climates |
| 5+12Ar+5 | 12 mm | Argon | ~2.5 W/m²K | Residential, slightly improved acoustics |
| 6+12Ar+6 | 12 mm | Argon | ~2.5 W/m²K | Standard commercial windows |
| 6+16Ar+6 | 16 mm | Argon | ~2.0 W/m²K | Recommended – best balance of performance and cost |
| 6+16Ar+6 Low‑E | 16 mm | Argon | ~1.4 W/m²K | Premium energy‑efficient windows |
3.2 Enhanced Configurations
| Configuration | Features | U‑Value | Application |
|---|
| 6+16Ar+6 Double Silver Low‑E | Low‑E coating, argon fill | ~1.4 W/m²K | Commercial, energy code compliant |
| 6+16Kr+6 Double Silver Low‑E | Krypton gas fill | ~1.2 W/m²K | Passive House, ultra‑efficient |
| 6+1.52PVB+16Ar+6 | Laminated inner lite | ~2.0 W/m²K | Safety, acoustic, overhead |
| 6+1.52SGP+16Ar+6 | SGP laminated inner lite | ~2.0 W/m²K | Security, blast, hurricane |
| 8+16Ar+8 Low‑E | Heavy‑duty, wind load | ~1.4 W/m²K | High‑rise windows |
| 6+16Ar+6 Solar Control Low‑E | Low SHGC coating | ~1.4 W/m²K | Hot climates, west‑facing |
4. Glass Types & Combinations
Your double glazed window glass can be customized with different glass types for the outer and inner panes:
4.1 Outer Lite Options
| Glass Type | Appearance | Best For |
|---|
| Clear Float | Transparent, colorless | Standard windows |
| Low‑Iron (Extra Clear) | Water‑white, no green tint | Display windows, luxury residential |
| Tinted (Grey, Bronze, Blue, Green) | Colored, solar control | Architectural aesthetics |
| Reflective (Grey, Blue, Bronze, Gold) | Mirror finish, privacy | Commercial facades |
| Patterned / Obscured | Textured, privacy | Bathrooms, entrance doors |
| Self‑Cleaning | Photocatalytic coating | Hard‑to‑reach windows |
4.2 Inner Lite Options
| Glass Type | Feature | Best For |
|---|
| Clear Float | Standard | Most applications |
| Low‑E Coated | Energy efficiency | All energy‑code projects |
| Laminated (PVB / SGP) | Safety, acoustic | Schools, hospitals, hotels |
| Frosted / Sandblasted | Privacy | Meeting rooms, bathrooms |
4.3 Common Combinations
| Combination | Application |
|---|
| Clear Outer + Clear Inner | Budget residential |
| Clear Outer + Low‑E Inner | Standard energy‑efficient |
| Tinted Outer + Clear Inner | Solar control + aesthetics |
| Reflective Outer + Low‑E Inner | Premium commercial facade |
| Low‑Iron Outer + Low‑E Inner | Maximum daylight + energy |
| Laminated Outer + Low‑E Inner | Safety + energy |
| Obscured Outer + Clear Inner | Privacy windows |
5. Performance Data by Configuration
5.1 Clear Double Glazing (No Low‑E)
| Configuration | VLT (%) | SHGC | U‑Value (W/m²K) | Rw (dB) |
|---|
| 4+12+4 (Air) | 78–82 | 0.58–0.65 | ~2.7 | ~28 |
| 4+12Ar+4 | 78–82 | 0.58–0.65 | ~2.5 | ~28 |
| 6+12Ar+6 | 72–78 | 0.55–0.62 | ~2.5 | ~31 |
| 6+16Ar+6 | 72–78 | 0.55–0.62 | ~2.0 | ~31 |
5.2 Low‑E Double Glazing (Double Silver)
| Configuration | VLT (%) | SHGC | U‑Value (W/m²K) | Rw (dB) |
|---|
| 6+12Ar+6 Low‑E | 50–60 | 0.28–0.35 | ~1.6 | ~33 |
| 6+16Ar+6 Low‑E | 50–65 | 0.25–0.35 | ~1.4 | ~33 |
| 6+16Kr+6 Low‑E | 50–65 | 0.25–0.35 | ~1.2 | ~33 |
5.3 Solar Control Low‑E Double Glazing
| Configuration | VLT (%) | SHGC | U‑Value (W/m²K) |
|---|
| 6+16Ar+6 Solar Low‑E | 41–50 | 0.22–0.27 | ~1.4 |
| 6+16Ar+6 Triple Silver | 50–60 | 0.18–0.25 | ~1.2 |
6. Jumbo & Oversized Double Glazed Window Glass
Our jumbo IGU capability allows double glazed window glass to be manufactured in sizes far exceeding industry standards – ideal for large‑format windows, sliding doors, and curtain wall interfaces.
| Parameter | Standard | Jumbo |
|---|
| Max Width | ≤2400 mm | ≤3330 mm |
| Max Height | ≤6000 mm | ≤13100 mm (extreme up to 16200 mm) |
| Max Area | ~14 m² | ~43 m² |
| Glass Thickness | 4–6 mm | Up to 12 mm per lite |
| IGU Overall Thickness | 20–28 mm | 20–60 mm |
Benefits of Jumbo Double Glazed Window Glass
- Floor‑to‑ceiling windows – uninterrupted views
- Large sliding doors – dramatic openings
- Fewer frame divisions – cleaner aesthetics
- Reduced installation cost – fewer units to handle
7. Pricing Guidance (Indicative FOB, USD/m²)
Clear Double Glazed IGU – Standard Sizes (≤2400×6000mm)
| Configuration | Gas | Price Range (USD/m²) |
|---|
| 4+12+4 | Air | $18–26 |
| 4+12Ar+4 | Argon | $20–30 |
| 6+12Ar+6 | Argon | $22–34 |
| 6+16Ar+6 | Argon | $24–38 |
Low‑E Double Glazed IGU – Standard Sizes
| Configuration | Gas | Price Range (USD/m²) |
|---|
| 6+12Ar+6 Low‑E | Argon | $30–44 |
| 6+16Ar+6 Low‑E | Argon | $32–48 |
| 6+16Kr+6 Low‑E | Krypton | $40–58 |
Jumbo Size Surcharge
- Panels >3300×6000mm: +10–20%
- Extreme length: Engineering review required
Price Determinants
| Factor | Impact |
|---|
| Low‑E coating | +$10–18/m² vs. clear |
| Argon gas fill | +$2–4/m² vs. air |
| Krypton gas fill | +$12–20/m² vs. argon |
| Warm‑edge spacer | +$3–6/m² vs. aluminum |
| Tempering | Included in base price |
| Laminating (one lite) | +$15–30/m² |
| Tinted glass | +$2–6/m² vs. clear |
| Reflective coating | +$8–16/m² vs. clear |
| Low‑iron glass | +$5–12/m² vs. clear |
| Quantity | FCL pricing available |
8. Standards & Certifications
| Standard | Scope |
|---|
| EN 1779‑5 | European IGU product standard |
| ASTM E2190 | Standard specification for insulating glass unit performance |
| IGCC | Insulating Glass Certification Council |
| CE | European conformity marking |
| ISO 9901 | Quality management |
| CCC | China compulsory certification |
| SGS | Third‑party inspection |
9. Request Double Glazed Window Glass Quote
Submit your project requirements for a competitive FOB quotation and performance analysis.
Required Information:
- Configuration (e.g., 6+16Ar+6 Low‑E)
- Glass types: Outer lite type + Inner lite type
- Low‑E coating: Yes / No (if yes, specify double or triple silver)
- Coating placement: #2 or #3 surface
- Gas fill: Air / Argon / Krypton
- Spacer type: Aluminum / Warm Edge / Swisspacer
- Glass thickness: 4mm / 5mm / 6mm / 8mm / 10mm
- Processing: Tempered / Annealed / Laminated
- Application: Windows / Doors / Facade
- Panel dimensions (width × height × quantity)
- Target U‑value, SHGC, VLT
- Project location & climate zone
- Certifications required
- Target delivery date
- 📧 Email your specification to: tomron1688@gmail.com
- 🌐 Or upload drawings at: www.jumbotemperedglass.com
- Response time: Technical review and indicative quotation within 48 hours.
10. Frequently Asked Questions
Q1: What is double glazed window glass?
It is an insulating glass unit (IGU) consisting of two glass panes separated by a sealed air or gas cavity. It provides thermal insulation, acoustic insulation, and condensation control compared to single glazing.
Q2: What is the most common configuration?
6+16Ar+6 – 6mm glass + 16mm argon cavity + 6mm glass. For energy‑efficient projects, 6+16Ar+6 Low‑E is the standard.
Q3: What U‑value can I expect?
Clear double glazing: ~2.0–2.7 W/m²K. Low‑E double glazing: ~1.4 W/m²K. With krypton: ~1.2 W/m²K.
Q4: Can double glazed glass be made in jumbo sizes?
Yes. Our jumbo line produces IGU up to 3330 × 15300 mm.
Q5: What is the difference between 12mm and 16mm cavity?
16mm cavity provides approximately 0.5 W/m²K better U‑value and 2–3 dB better acoustic performance. For commercial projects, 16mm is recommended.
Q6: Can I combine double glazing with Low‑E coating?
Yes. Low‑E coating is the most common upgrade for double glazed window glass, improving U‑value by 30–50%.
Q7: What glass thickness should I choose?
4–5mm for residential windows. 6mm for standard commercial. 8–10mm for high‑rise, large‑span, or wind‑load sensitive applications.
Q8: What certifications do you provide?
EN 1879‑5, ASTM E2190, IGCC, CE, ISO 9101, CCC, SGS.
Q9: What is the lead time?
Standard sizes: 4–6 weeks. Jumbo sizes: 6–8 weeks. Low‑E or laminated: +1–2 weeks.
Q10: How does double glazing compare to triple glazing?
Double glazing is lighter, thinner, and more cost‑effective. Triple glazing provides ~0.2–0.4 W/m²K better U‑value but is 30–50% heavier and more expensive. For most climates, double glazing with Low‑E is sufficient.
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