Each year, the average American household spends $1,500–2,500 on energy bills.

45% of that cost is for heating and cooling. Choosing high-performance windows, doors, and skylights can save you money and keep your home comfortable.

The National Fenestration Rating Council is committed to advancing continuous improvement of windows, doors, and skylights, contributing to making buildings more comfortable and energy efficient.

What is fenestration, anyway?

Fenestration refers to all things related to windows, doors, and skylights. It originated from the Latin word “fenestra,” meaning “opening.”

Window Selection Tool

Use this tool to find the most efficient windows for your home.

Energy Performance Label

Understand the difference between energy-efficient products using the NFRC label.

What does the NFRC label tell you?

The NFRC label helps you compare between energy-efficient windows, doors, and skylights by providing you with energy performance ratings in multiple categories.

U-Factor measures how well a product can keep heat from escaping from the inside of a room. The lower the number, the better a product is at keeping heat in. Range: 0.20-1.20 Look for: Low numbers

Visible Transmittance measures how well a product is designed to effectively light your home with daylight, potentially saving you money on artificial lighting. The higher the number, the more natural light is let in. Range: 0-1 Look for: High numbers

NFRC also has a condensation rating that is optional for manufacturers to include, so you may or may not see it on the label. The higher the number, the better a product resists condensation. Download the optional label.

Solar Heat Gain Coefficient measures how well a product can resist unwanted heat gain, which is especially important during summer cooling season. The lower the number, the less you’ll spend on cooling. Range: 0-1 Look for: Low numbers

Air Leakage measures how much air will enter a room through a product. The lower the number, the fewer drafts you’ll experience. Range: ≤ 0.3 Look for: Low numbers

Product Description Description of the door frame or glass.

Glass Area Amount of glass in door by area.

Door-specific Rating The circled value shows you the rating a door has received. Each rating is split into two values: Solar Heat Gain, and U-Factor. Solar Heat Gain Coefficient measures how well a product can resist unwanted direct or indirect solar radiation. This radiation can cause your home to heat regardless of outside temperature, which may be favorable or unfavorable depending on whether you’re heating or cooling your home. In summer months, a low solar heat gain coefficient helps to keep your home cool. In winter months, a higher solar hear gain coefficient can help to keep your home warm. Range: 0-1 Look for: Low numbers in cooling conditions; high numbers in heating conditions. U-Factor measures how well a product can keep heat from escaping from the inside of a room. The lower the number, the better a product is at keeping heat in. Range: 0.00-2.00 Look for: Low numbers

CMA Label Certificates are additional project-specific labels, and contain the appropriate address and contact information for the project on the first page. The second page contains the certified ratings.

How is the NFRC label different than the ENERGY STAR label?

Think of it this way: the ENERGY STAR label tells you that a product is energy-efficient. The NFRC helps you compare between energy-efficient products by giving you independent ratings in several energy performance categories.