Energy Star & NFRC

ENERGY STAR®: Getting More for Your Money

energystarmap09Will I Be Able To Find The Style And Type Of Window I Want?

When choosing an ENERGY STAR® window or door, you don’t sacrifice comfort, versatility or style. Vanguard Windows feature ENERGY STAR® approved glass in all our window and patio door options.

What Other Advantages Can I Expect From An Energy Star Window?

Some home furnishings and décor can actually suffer a kind of sunburn when continuously exposed to too much daylight. The ultraviolet (UV) rays from the sun can cause fading and degradation of many materials and dyes found in upholstery, carpet, artwork, wood or paint. Our exclusive Ultra-U glass, available for all Vanguard windows, can reduce harmful sun damage by up to 75 percent, giving greater protection to your interiors. ENERGY STAR® windows, by virtue of their design, eliminate draftiness and resist condensation for greater comfort. A well-insulated window also diminishes sound transmission.

How Can I Get The Most Energy Efficient Product For My Climate?

ENERGY STAR® performance requirements for windows and doors are tailored to fit the energy needs of the country’s different climate regions – Southern, Northern and Central. The ENERGY STAR® Climate Region Map gives you clear guidelines for determining which windows and doors will do the best job to help reduce heating and cooling costs in your region – and your home. To be sure, crosscheck your window selection with the Climate Region Map on each ENERGY STAR® label. In all cases your decision is simplified; Vanguard products meet performance requirements for all three regions.

The Label Tells the Real Story

Designed to help consumers measure and compare energy performance of different window brands, The National Fenestration Rating Council (NFRC), provides consistent benchmark ratings on performance characteristics of different window and door brands, allowing you to compare different brands by the same fair standards.

Many manufacturers may make claims as to how their products perform, but they may not provide you with the actual printed copy of the NFRC label. Without the label, there’s no guarantee as to how or where the products were tested. With Vanguard Windows, we’ve invested time and money to provide consumers certified performance data so you can be certain that our products will perform for you.

Energy performance rating

energy-label09Interpreting U-Factor Ratings

U-Factor Ratings typically range between .20 and 1.20. The lower the U-Factor the less energy you will use to heat your home. This performance and energy efficiency will likely result in overall cost savings for you.

Visible Transmittance

Visible Transmittance, commonly referred to as VT, measures the amount of light that enters through your window. VT ratings typically range between 0 and 1. The higher the visible light transmittance, the more light that is transmitted through your window.

Solar Heat Gain Coefficient ­ Summer

A low Solar Heat Gain Coefficient, commonly referred to as SHGC, equates to less solar radiation admitted through your window. SHGC ratings typically range between 0 and 1.

A lower Solar Heat Gain Coefficient rating means your home will remain cooler during the summer months. More comfort means more money in your wallet for summer fun.

Air Leakage

Windows are tested for air infiltration to see if they allow air to pass through, and are then assigned a number of either 0.3, 0.2, or 0.1. The lower the number, the less drafts you’ll have in your home. The lowest number that the U.S. Department of Energy assigns to air filtration is 0.1. Any window with an air leakage number above 0.3 is considered to have failed the mandated air leakage test. Any number lower than a 0.1 not only passes but exceeds the qualifications that are set by the DOE testing organizations.


This data is accurate as of May 1, 2012. Due to ongoing product changes, updated test results, or new industry standards or requirements, this data may change over time. Ratings are for sizes specified by NFRC for testing and certification. Ratings may vary depending on use of tempered glass, different grid and decorative glass options, glass for high altitudes, and coastal applications.