Windows Designed for Performance and Beauty
Our expertly crafted windows offer superior durability, energy efficiency, and timeless style — enhancing the comfort and value of any home.
Find a sustainable solution based on your climate zone
If you require an ENERGY STAR rated product for your project, it is very important to select the proper performing glass option for the location in which it will be installed. Use the Energy Star Climate Zone Finder to determine your climate zone.

Frequently Asked Questions
What is ENERGY STAR Version 7?
Recently, the U.S. Environmental Protection Agency’s (EPA) ENERGY STAR® program released its final version 7 specification for Residential Windows, Doors, and Skylights that establish higher energy-efficiency benchmarks for products to earn EPA’s coveted ENERGY STAR certification. This new specification outlines more demanding certification criteria of various fenestration products.
The energy performance of windows is essential to overall building efficiency and its environmental impact. More efficient windows will reduce your home’s carbon emissions on day one, independent of what source of energy is used to heat and cool your building. Although windows only account for about 10% of an average home’s surface area, approximately 35% to 45% of the heat homes lose in winter months pass through windows. More insulative windows, like the industry-leading models that the new ENERGY STAR criteria will certify, can bring those losses down considerably, which saves energy and money.
When do ENERGY STAR Version 7 certification requirements go into effect?
ENERGY STAR Version 7 certification requirements went into effect October 23, 2023. All fenestration products bearing the Energy Star label must adhere to the new requirements.
Can ENERGY STAR windows help me qualify for tax incentives or rebates?
Yes! Installing ENERGY STAR certified windows may make you eligible for federal tax credits or local utility rebates. Be sure to check with your tax advisor or utility provider to learn about the incentives available in your area.
Why is there condensation on my window, and does it mean there's a problem?
Condensation on the indoor or outdoor glass surface is typically caused by temporary environmental factors (like high humidity or sudden temperature shifts) and is not a sign of a product defect. However, if you notice condensation between the panes of glass, this may indicate a seal failure or crack, and the window may need replacement.
Why should I choose vinyl windows?
Vinyl windows offer excellent energy efficiency, helping lower utility bills and improve comfort year-round. They’re also low-maintenance, durable, versatile in design, and provide good sound insulation.
Do Westlake Royal Window Solutions products meet ENERGY STAR Version 7 requirements?
Yes! We have several ENERGY STAR certified window and sliding glass door products available including standard, impact and STC (Sound Transmission Class) grades. These support the Southern, South-Central and North-Central climate zones and are available from all four of our manufacturing plants:
Magnolia collection (Baldwin, GA)
Krestmark collection (Dallas, TX)
Legacy collection (Houston, TX)
Are ENERGY STAR Version 7 certified windows mandatory?
ENERGY STAR version 7 certified windows are not mandatory. However, some builders and zoning districts may require the installation of ENERGY STAR certified windows. Additionally, homeowners may choose ENERGY STAR certified windows for energy savings as well as potential tax credits.
How do I know if my windows need to be replaced with ENERGY STAR models?
If your current windows are drafty, have visible condensation, or are more than 15-20 years old, it may be time to upgrade to ENERGY STAR windows. Replacing old windows with high-efficiency options can improve comfort, reduce energy bills, and increase your home’s value.
Can I apply window tint film to improve energy efficiency?
Applying tint film can alter the original engineering and performance of the insulated glass and will void the product warranty. Although it might reduce solar heat gain, it can disrupt the certified insulating properties of the glass unit. Always consult with an expert before making modifications.
What the NFRC label tells you about Westlake Royal Windows
The NFRC label lists important fenestration performance ratings and can be found on all of Westlake Royal Windows’ products. Our label lists the performance ratings in four main categories: U-Factor, Solar Heat Gain Coefficient (SHGC), Visible Transmittance (VT) and Air Leakage.
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