Your Guide to Energy Efficient Windows

By: Architectural Visions

Energy efficient windows will not only reduce your home’s energy costs, but they will also ensure your home feels more comfortable, regardless of the outside temperature. Windows that are energy efficient are designed to achieve long-term performance and be cost-efficient, irrespective of your climate. Familiarizing yourself with the ins and outs of energy efficient windows will bring more clarity to your investment.

This guide will break down everything you need to know about energy efficient windows, including:

  • What makes a window energy efficient
  • The metrics associated with energy efficient windows
  • The benefits of energy efficient windows
  • How to tell if your windows are energy efficient
  • How to make your windows more energy efficient
  • What window brands are known for energy efficiency

What makes a window energy efficient?

Replacing your windows with energy efficient versions will save money long-term, as they will help save on energy costs. Energy loss through windows can be responsible for up to 30% of residential heating and cooling costs. Investing in energy efficient windows can help minimize these costs. Whether you’re looking to prevent the heat from coming in or escaping, energy efficient technology can do this, regardless of your climate.

The following features are important to consider when you’re looking to invest in energy efficient windows:

  • Type of window frame. The frame is the window’s foundation. Materials to consider include fiberglass, vinyl, aluminum, wood, composite. Different frame materials can impact how a window retains energy (i.e., vinyl has more insulation than wood). The more durable the frame, the less likely it is to warp, which will help prevent drafts. Foam-filled frames can also provide extra insulation.
  • The number of panes of glass. Energy can escape a single-pane window, but energy efficient windows with two or three panes of glass windows can prevent this. Multiple panes provide insulation and help block heat transfer.
  • Low emissivity (Low E) coating. To help heat from escaping your windows in the winter, a thin metallic layer, known as a Low E coating, is applied to the window’s exterior pane. In the summer, this keeps the outside heat from coming inside.
  • Gas fills. Gas fills in between the panes of glass provide additional insulation.
  • Spacer. A spacer goes in between the glass panes to create a seal and reduce heat transfer.
  • Weatherstripping. Weatherstripping goes along the edges of the window to create a seal that keeps drafts out. Higher quantities of high-quality weather stripping result in having energy-efficient windows.
  • Professional installation. Properly installed windows will ensure they are installed correctly and will maximize the energy-efficiency. A professional installation will also guarantee that they fit perfectly into your home without any leaks or gaps.

What measurements are important for energy efficiency? 

Several metrics are associated with energy efficient windows that can help you better understand how energy efficient your windows are. Below are several standard energy performance metrics.

  • Visible transmittance (VT) is how sensitive sunlight is to the eye, transmitted through a window, door, or skylight. A window with a higher VT transmits more light. VT is a number between zero and one. A VT is determined by how much light your home requires or how much glare you need to reduce.
  • U-factor is another standard metric that rates how a window, door, or skylight conducts heat flow. Windows with a lower U-factor are more energy efficient.

What are the benefits of energy-efficient windows?

One of the most significant benefits of investing in energy efficient windows is to save money on your heating bills in the winter and air conditioning bills in the summer. It’s estimated that 30% of heating and cooling costs come from energy loss through windows. So if you’re replacing single-pane windows with energy efficient options, you can save hundreds of dollars per year.

Energy efficient windows will also provide higher comfort levels when you’re at home by keeping you cooler during the hot summer months, and warmer as the temperatures outside drop. Additionally, you will benefit from reduced outside glare, decreased sun damage to your furniture, and energy efficient windows can even increase your home’s resale value.

Energy efficient windows benefit not only your bank account and personal comfort but also the environment. ENERGY STAR certified windows, doors, and skylights can reduce carbon footprints by an average of 12 percent nationwide.

Replacing your windows with energy efficient alternatives . Specific improvements qualify for the residential energy efficient property credit for homeowners, and energy efficient windows are considered a qualified energy efficiency improvement. You may claim a credit for 10% of the cost of eligible energy efficiency improvements, subject to the $500 credit limit.

How to tell if your windows are energy efficient?

The easiest way to determine if your windows are energy efficient is to look for an ENERGY STAR label. For a window to qualify as an ENERGY STAR window, it must be:

Features that make a window energy efficient include:

  • Qualify frame materials
  • Number of panes
  • Low-E glass
  • Gas fills
  • Warm edge spacers

How to add to your window’s energy efficiency

Even if your windows are energy efficient, there are additional steps you can take to add to your window’s energy efficiency. Increasing your windows’ energy efficiency can be especially helpful if you live in a climate that gets extremely cold in the winter or extremely hot in the summer.

Insulating curtains can be helpful; however, is important to keep them open during daylight hours. When you cover the windows with insulated curtains, you’re also keeping out the sun’s warmth. However, leaving the curtains open during the daytime and closing them at night will allow the sun to shine through in the day and help insulate the windows overnight.

Another option is to apply a window insulation film. This plastic film typically comes in a kit so you can apply it to your windows yourself. The film can reduce UV rays, help prevent warm air from escaping, and minimize the amount of cold air that enters through the windows.

What window brands are known for energy efficiency?

Not all window brands are created equal, so it’s essential to select a brand that is known for energy efficiency. Several window brands known for energy efficiency are Marvin and Western Window Systems.

These brands use materials and insulating glass that are fundamental to creating energy efficient window designs. For example, one of the best window materials is fiberglass, specifically a fiberglass called Ultrex. Ultrex, which Marvin created, offers extreme durability and strength. Marvin has been in business for more than 100 years.

If you’re looking to reduce your energy costs while being more comfortable at home, investing in energy-efficient windows may be right for you. By understanding what makes a window energy efficient and the brands that are known for creating high-quality, energy efficient windows, you can make a smart investment that will benefit your bank account, comfort and environment. Whether you have sweltering summers or bitterly cold winters, energy-efficient windows will achieve the long-term performance you need.

Shop for energy-efficient windows at AVI Windows & Doors

Is it time to improve your home’s energy efficiency? We carry top energy-efficient window brands and our window experts are trained in environmentally sensitive practices, allowing you to experience green construction firsthand.

Please don’t hesitate to reach out to us by phone, online, or in person at one of our southeast locations today: