Knowledge Seminar Series : High Performance Glass October 18, 2017 - PowerPoint PPT Presentation

Knowledge Seminar Series : High Performance Glass October 18, 2017 Jim Larsen Director, Technology Marketing

Cardinal Glass Divisions • FG: flat glass • TG: tempered (safety) glass • CG: coated glass (low-E) • LG: laminated glass (safety & hurricane) • IG: insulating glass (2 and 3 pane units)

Winnipeg Glass Design Priorities • Cold weather: Design for low U-Factor – Reduce heat loss – Warmer glass surface at winter night • Winter sun on South elevation – Potential for passive design • Summer sun on East & West elevations – Beware discomfort due to overheat

5 months below freezing

5 months below freezing

Low-E units are warm on winter night. Clear glass is cool.

Winter Sun: 8 hours of Daylight

Summer Sun: 16 hours of Daylight

High solar gain low-E is hot in sunlight

Energy Terms • U-Factor (heat loss) • SHGC: Solar Heat Gain Coefficient • VT: Visible Light Transmission – Aesthetic (clarity, color) – Daylighting energy mostly in commercial

Traditional Energy Solutions for Windows 1. Add layers to insulate glass – Single, double, triple, etc. 2. Change frame material – Metal, thermal break, wood/vinyl/fiberglass – Add warm-edge spacer 3. Add tinted or reflective glass – Absorb sunlight with tinted glass – Reject with reflective glass

The Rule of Panes Each layer of glass in a multi-pane unit adds approximately 1 “R” to the insulating value (Inch-Pound R-Value) Low-E coatings and gas fills displace layers of glass

Lots of Panes Single Pane ~ R1 Double Pane ~ R2 Triple Pane ~ R3 Quad Pane ~ R4 ……… “Octo-Pane” ~ R8

“R2” Glass Window U ~ 0.50 (2.8)

“R4” Glass Window U ~ 0.35 (2.0)

Less “Pain” with Low-E • Single Pane ~ R1 • Double Pane ~ R2 • Triple Pane ~ R3 • Quad Pane ~ R4 • 2 Pane + Low-E ~ R3 • 2P + Low-E + Argon ~ R4

More Low-E and More Panes • Single Pane ~ R1 • Double Pane ~ R2 • Triple Pane ~ R3 • Quad Pane ~ R4 • 2 Pane + Low-E ~ R3 • 2P+Low-E+Argon ~ R4 • Triple w/2 Low-E + Argon ~ R8

Non-Metal Window U ~ 0.30 (1.7) 2 Pane + Warm Edge + Low-E + Argon

Traditional Options for Solar Control Glass Tinted – Adds color to “body” of glass – Absorbs sunlight and re-radiates to exterior Reflective – Mirror appearance – Reflects sunlight out

Clear Glass Window SHGC ~ 0.60

Window SHGC

The Solar Spectrum 3% 45% 52%

2P Clear: Window SHGC ~ 0.6

2P Tinted: Window SHGC 0.4 – 0.5

A New Option for Solar Control Glass Tinted – Adds color to “body” of glass – Absorbs sunlight and re-radiates to exterior Reflective – Mirror appearance – Reflects sunlight out Spectrally Selective Low-E – Clear glass appearance with solar control – Reflects solar infrared (invisible to human eye)

High Solar Gain Low-E: Window SHGC ~ 0.5

Medium Solar Gain Low-E: Window SHGC ~ 0.3

| Low-E | Clear Glass Med Solar | High Solar

Low Solar Gain Low-E: Window SHGC ~ 0.2

Dual Pane Insulating Glass

High Solar Gain Low-E on Surface 3 = Hot in Sunlight!

Triple Pane Insulating Glass

Triple Pane Coating Recommendations • Avoid low-E on center pane (#3 or #4) • Use high solar gain low-E on #5 for best visible characteristics and lowered risk of thermal stress breakage • Select High, Medium, or Low solar gain low-E for #2 surface (orientation specific)

Thank you! Any questions?