Energy Efficient Windows and Doors



Watch the video to learn terms for energy efficient windows and doors.

Selecting your new construction or replacement windows and doors can be a daunting task with so many different materials, styles, colors, construction methods, and hardware.  Beyond the beauty of your new windows and doors, check the energy efficiency to ensure a product that will perform.  


ENERGY STAR® is the symbol for energy efficiency.  It is backed by the U.S. Department of Energy and the Environmental Protection Agency (EPA) who provide simple, credible, and unbiased information that consumers can rely on to make well-informed decisions.  The EPA  ensures that each product that earns the label is independently certified to deliver the energy performance and savings that consumers can expect. Energy-efficient windows and doors are constructed to reduce heat exchange and air leaks, which means not as much energy is used to heat or cool a space. ENERGY STAR has a map of zones across the U.S.A, with window and door standards for each zone’s climate. Houston, Austin, and most of the Texas Hill Country is in the Southern Zone.   The government also issues tax credits  for energy efficiency.  

The Inflation Reduction Act of 2022 extends residential energy efficiency tax credits through 2032.  Tax credits for windows and doors are 10% of the cost (not including installation), up to $500, however windows are currently capped at $200.  In 2023, the tax credits have been adjusted to an aggregate of $600 for exterior windows and $250 for each exterior door, or $500 aggregate for exterior doors. 


While the ENERGY STAR label indicates that a product is energy efficient, the National Fenestration Rating Council (NFRC) compares energy efficient products by breaking down a product’s energy performance.  Fenestration is defined by Merriam-Webster Dictionary as the arrangement, proportioning, and design of windows and doors in a building.  There are four main ratings on the NFRC label:  U-Factor, Solar Heat Gain Coefficient, Visible Transmittance, and Air Leakage.  


The U-Factor measures how well a window or door keeps heat from escaping inside a room.  The lower the number, the better a product keeps heat in.  The measurement ranges from 0.20 to 1.20.  Look for low numbers. 

Solar Heat Gain Coefficient

Resisting heat gain is important, especially during the summer cooling season.  Solar Heat Gain Coefficient measures how well a product resists heat gain.  The measurement ranges from 0 to 1, with a lower rating being preferable.  

Visible Transmittance

How well a window or door is designed to effectively light a home with daylight is measured by visible transmittance. The higher the number with a range 0 to 1, the more natural light is let in.

Air Leakage

Worried about drafts? Air leakage measures how much air enters a room through a window or door.  With a range less than or equal to 0.3, the lower the number, the fewer drafts.  


Although it is not always included on the NFRC label, condensation is an optional rating for manufacturers to include on the product.  The higher the number, the better a window or door resists condensation.  


The American Architectural Manufacturers Association (AAMA) and the Insulating Glass Manufacturers Alliance (IGMA) united to form the Fenestration and Glazing Industry Alliance (FGIA).  The AAMA Product Certification is the original third-party window and door performance program. The AAMA Certification Label signifies that a sample of the product has been verified as conforming to the standards’ requirements through independent laboratory testing as well as follow-up onsite inspections of the manufacturer’s product line.

The AAMA Gold Label Certification Program is coveted by manufacturers.  The Gold Label is accepted or required by many federal, state and municipal building codes and administrators as an indication of product quality.  Various AAMA programs ensure quality for vinyl and fiberglass window and door profiles, verified components, insulated glass, and laboratory accreditation.  FGIA also acts as an Inspection Agency for the NFRC’s thermal certification program.  


The U.S. Green Building Council (USGC) has a certification tool Leadership in Energy and Environmental Design (LEED) which provides a framework for healthy, efficient, carbon and cost-saving green buildings. Globally recognized as a symbol of sustainability achievement, the LEED rating system awards points to projects which adhere to prerequisites and credits that address a number of factors including energy, materials, health and indoor environmental quality.  


There is a high bar set for window and door manufacturers to provide quality, energy efficient products.  Going well beyond the government ENERGY STAR standards, the window and door fenestration industry has set higher standards through the NFRC, AAMA, FGIA, and LEEDS, to name a few.  Manufacturers continually create, improve and enhance their products to stay ahead of the curve and bring the solutions homeowners, architects, interior designers, and building professionals want for their window and door projects. 

Renaissance Windows and Doors represents top manufacturers to offer our clients innovative, high quality windows and doors for new construction, replacement and remodel projects. Our team of experts can guide you to the best solution for your new windows and doors.  “Selection.  Expertise. Service at Every Step.” –that’s the Renaissance promise.  Call today 713-863-9988.