Brennan Windows | Replacement Window General Knowedge | Energy reducing windows in Dallas / Fort Worth

Buying windows can be very complicated. There are dozens of manufacturers that make dozens of brands. Then there are wood windows, vinyl windows, aluminum windows, and fiberglass windows. Then there is hard LowE, soft LowE, LowE/2 (energy efficiency of glass), different gas packages, and different Solar Heat Gain Coefficients, U-Values and DP ratings. Are the windows Energy Star rated? Do they meet NFRC requirements for your climate? Where does it all end?

Brennan Windows eliminates the guesswork. All of the windows we sell are Energy Star compliant and meet NFRC ratings for your climate. Also, our windows provide a limited lifetime manufacturer’s warranty. See our Warranty page for more information.

If you want more knowledge about the complexity of windows and Energy Star ratings or the NFRC certification, keep reading.

When you’re choosing new or replacement windows, it’s always good to look for the Energy Star rating.

The U.S. Environmental Protection Agency (EPA) launched the Energy Star program in 1992 to protect the environment through energy efficient products and procedures. In order to receive an Energy Star rating, products falling under 50 home and office categories must meet strict energy conservation guidelines set by the U.S. Department of Energy, which partnered with the EPA on Energy Star in 1996.

The first Energy Star labeled products were computers and monitors, but this line quickly expanded to include printers, fax machines, residential appliances and fixtures, windows and even new homes and buildings. According to Energy Star, Americans saved enough on Energy Star products in 2006 alone to save $14 billion on utility bills and avoid greenhouse gas emissions equivalent to that released by 25 million cars.

In addition to providing a rating system, Energy Star helps organizations and consumers practice informed decisions, delivering technical information and tools through more than 9,000 partnerships in the public and private sector. Energy Star’s efforts have led to more widespread use of LED traffic lights, efficient fluorescent lighting, energy management systems for office equipment, and low standby energy use.

Consumers can look for the Energy Star label when shopping for a new home or searching for new home products, such as refrigerators, dishwaters, and home heating systems. The label will show the product’s typical yearly energy usage. Examples of Energy Star labeled products include full-sized dishwashers that conserve 493 gallons of water per year and washing machines that save over 12,000 gallons of water per year. Appliances with the Energy Star rating average 10 to 20 percent higher energy efficiency than their non-rated counterparts. Items labeled “Energy Efficient” may have low energy emissions without meeting the standards to be rated as an Energy Star product.

The energy performance of all ENERGY STAR qualified windows, doors, and skylights must be independently tested and certified according to test procedures established by the National Fenestration Rating Council (NFRC).

NFRC is a third party, non-profit organization that sponsors certified rating and labeling programs to help consumers compare the energy and performance features of windows, doors, and skylights.

NFRC's programs do not distinguish between “good” and “bad” windows, set minimum performance standards, or mandate performance levels. This is where ENERGY STAR comes in. ENERGY STAR enables consumers to easily identify NFRC-certified products with superior energy performance.

Read the NFRC label and see for yourself why a window with this label earns the ENERGY STAR in all Climate Zones.

Performance Ratings

The NFRC label, which can be found on all ENERGY STAR qualified windows, provides performance ratings in a number of categories:

U-Factor measures the rate of heat transfer and tells you how well the window insulates. The lower the U-Factor, the better the window insulates. U-Factor values generally range from 0.25 to 1.25.

Solar Heat Gain Coefficient (SHGC) measures the fraction of solar energy admitted and tells you how well the product blocks heat caused by sunlight. The lower the SHGC, the less solar heat the window transmits. SHGC is measured on a scale of 0 to 1; values typically range from 0.25 to 0.80.

Visible Transmittance (VT) measures the amount of light the window lets through. The higher the VT, the more light you see. VT is measured on a scale of 0 to 1; values generally range from 0.20 to 0.80.

Air Leakage (AL) measures the rate at which air passes through cracks in the window. AL is measured in cubic feet of air passing through one square foot of window area per minute. The lower the AL value, the less air leakage. Most industry standards and building codes require an AL of 0.3 cfm/ft².

Condensation Resistance measures how well the window resists water build-up. The higher the condensation resistance factor, the less build-up the window allows. Condensation Resistance is scored on a scale from 0 to 100. The Condensation Resistance rating is useful when comparing different products. ENERGY STAR qualification is based on U-Factor and SHGC ratings only.

Characteristics:	Aluminum	Vinyl	Wood Clad	Wood
Durability	Durable	Very Durable	Vinyl Clad: Very Durable Aluminum Clad: Durable	Damage associated with moisture is more of a concern
Sturdiness	Four times that of Vinyl and 23 times Wood	Considerably Strong	Exterior Frame: Quite Strong Interior Frame: Slightly Weaker	Slightly Weaker
Energy Efficiency	Energy efficiency is of concern due to aluminum's ability to conduct heat and cold	Quite Efficient	Wood Clad is energy efficient	Terrific Insulator
Maintenance	Fairly Low Maintenance	Typically Maintenance Free	Low Maintenance	Regular maintenance is required
The Design	A pleasing palate of colors that will accentuate your home	Flexible and streamlined, but with more limited color options	Exterior: The designs are based on aluminum or vinyl Interior: Designs determined by natural wood choice	Singular designs & natural beauty of wood provide limitless options
Cost	All price ranges available - fits any budget	All price ranges available - fits any budget	Medium to High Priced	Medium to High Priced