Energy Efficiency

One of the best things you can do to save money on your energy bill is to install energy efficient windows. Heat gain and heat loss through windows are responsible for 25%–30% of residential heating and cooling energy use.

If you are selecting windows for new construction or are replacing existing windows, it’s important to choose the best quality of window or door you can afford that work best for your home.

There are several decisions to make when it comes to the type of windows you purchase and the type of window replacement that will fit your needs. You will need to consider features, design, energy use and labeling, warranties, and most of all proper installation.

Look for the ENERGY STAR label when buying new windows. Then review ratings on the energy performance label from the National Fenestration Rating Council (NFRC) to find the most efficient windows for your needs.

NFRC ratings are included on all ENERGY STAR certified windows and provide a reliable way to determine a window’s energy properties and compare products.

Window Selection Tips

• Look for the ENERGY STAR and NFRC labels.
• In colder climates, consider selecting gas-filled windows with low-e coatings to reduce heat loss. In warmer climates, select windows with coatings to reduce heat gain.
• Pay attention to fire code in your area.
• Choose a low U-factor for better ther­mal resistance in colder climates; the U-factor is the rate at which a window conducts non-solar heat flow.
• Look for a low solar heat gain coef­ficient (SHGC). SHGC is a measure of solar radiation admitted through a window. Low SHGCs reduce heat gain in warm climates.
• Select windows with both low U-factors and low SHGCs to maximize energy savings in temperate climates with both cold and hot seasons.
• Look for whole-unit U-factors and SHGCs, rather than center-of-glass U-factors and SHGCs. Whole-unit numbers more accurately reflect the energy performance of the entire product.
• Sound performance is classified as an STC rating.

Learn more about energy performance ratings for windows.

Window Installation

Even the most energy-efficient window must be properly installed to ensure energy efficiency and comfort. Window installation varies depending on the construction of the house (wood, masonry, etc.), the exterior cladding (wood siding, stucco, brick, etc.), and the type of weather-restrictive barrier.

The Door and Window Consultants are trained professionals and install all doors and windows according to manufacturer’s instructions for proper performance.

Content provided by Department of Energy