Window quotes come with a stack of numbers and acronyms. Here’s what each rating means and how to spot which low e glass package actually performs in Texas heat.
Measures how well the window prevents heat transfer. Lower numbers mean better insulation performance.
Indicates how much solar heat passes through the glass. Lower values help reduce summer heat buildup.
Shows how much natural light enters your home. Higher numbers mean brighter interiors.
A microscopically thin metallic layer applied to the glass that reflects heat while allowing natural light to pass through. It keeps interiors cooler in summer and warmer in winter without darkening your home, the single most important upgrade in modern window glass.
Modern low e windows are double pane, two glass panes sealed together with an air or argon gas space between them. The low e coating is applied to one of the inner glass surfaces, where it's protected from weather and wear.
Argon gas is placed between the panes of a double pane window to slow heat movement more effectively than air. It improves insulation performance without affecting clarity and it's standard in every Cardinal LoĒ package we install.
Low e glass uses ultra-thin metallic coatings to control heat transfer. In summer, the coating reflects infrared heat back outside. In winter, it reflects interior warmth back into the room. Paired with argon gas between the panes, it reduces HVAC strain and improves comfort year-round in Plano homes
| Glass Type | U-Factor | SHGC | VT | UV Block |
|---|---|---|---|---|
| LoĒ-340 | 0.25 | 0.18 | 39% | 98% |
| LoĒ³-366 | 0.29 | 0.27 | 65% | 95% |
| Quad LoĒ-452² | 0.24 | 0.22 | 70% | 99% |
| LoĒ-i89 | 0.29 | 0.25 | 89% | 86% |
Certified by the NFRC. Browse official database.
Every Texas home has different sun exposure, room layouts, and comfort needs. Cardinal LoĒ packages let us match the right glass to your home’s orientation. Here’s how each option performs.
Not sure which package fits your home?
We walk you through every option during your free consultation.
LoĒ-i89 is a clear interior coating applied to the inside surface of the glass. When paired with LoĒ-366, it improves insulation performance and delivers near triple-pane efficiency in a dual-pane unit.
• Improves U-Factor without reducing visible light
• Reflects interior heat back into the home during winter
• Ideal upgrade for homeowners prioritizing maximum insulation
Engineered for strong south and west sun exposure. Helps keep hot rooms cooler, reduces glare, and protects flooring and furnishings from UV damage.
• High solar heat rejection
• Excellent for west-facing and large exposure windows
• Subtle tint that improves comfort without darkening the room
The most versatile glass package for North Texas homes. Delivers strong summer heat control while maintaining clear, neutral views and comfortable daylight.
• Excellent solar heat rejection for hot climates
• Neutral, clear appearance with no heavy tint
• Blocks up to 95% of damaging UV rays
• Ideal for most standard east, west, and south exposures
Designed for homeowners who want maximum efficiency without sacrificing natural light. Combines low U-Factor insulation with strong solar heat control for superior comfort in demanding exposures.
• Lower U-Factor for improved year-round insulation
• Excellent heat control with bright, natural daylight
• Enhanced UV protection to reduce interior fading
• Premium upgrade for large window walls and high sun exposure homes
Optional upgrades to enhance your low e glass package, including self-cleaning coatings, sound reduction, and decorative privacy options.
An advanced coating activated by sunlight that helps rainwater rinse away dirt and mineral buildup, keeping your windows cleaner with less maintenance.
Engineered with offset glass thickness and acoustic layers to help reduce outside noise while adding strength and security.
Add privacy or style while keeping your home bright. Perfect for baths, entryways, and sidelites.
Two often-overlooked details that affect how your windows arrive and how they perform long-term: the Endur IG spacer between the panes and the Preserve film that protects the glass on its way to your home.
Engineered to reduce heat transfer around the perimeter of the glass where most energy loss occurs.
• Reduces edge condensation
• Improves overall insulation performance
• Helps extend seal life
• Supports long-term durability
A factory-applied protective layer that shields glass during shipping and installation, ensuring your windows look pristine on day one.
• Protects against scratches and debris
• Removed cleanly after installation
• Helps deliver a spotless final result
• Reinforces installation quality
Low-E glass reflects infrared heat to keep homes cooler in summer and warmer in winter. It filters out UV rays that cause fading while maintaining natural daylight and clear views.
When installed correctly, Low-E windows can lower heating and cooling bills by up to 30%. Our FGIA-certified installation ensures the insulation value you pay for actually performs in real conditions.
Not at all. Today’s advanced coatings, like Cardinal® LoE-366 and LoE-452+, provide excellent heat rejection with a clear, neutral appearance. This means no heavy tinting or mirror effect.
No. Each type of Cardinal® Low-E glass is engineered for specific conditions. For example, LoE-340 blocks intense sun on west-facing windows, while LoE-366 balances year-round comfort. We help you select the right glass package for your home’s exposure and energy goals.
Cardinal’s® Low-E coatings are sealed within the glass unit, protecting them from oxidation and wear. With proper installation and maintenance, your energy performance will last the lifetime of the window.
Recent projects showcasing professionally installed, energy-efficient windows in a variety of home styles and settings.
Our certified team is here to help you choose the right windows for your home with honest guidance, no pressure, and expert answers every step of the way.
