Absolutely Everything You Need to Know About Energy Efficient Windows

If you are looking at saving on heating or air conditioning in your home, energy efficient windows may be the answer, but are they all they're cracked up to be? Energy efficient windows Beautiful window with shutters and curved, windowsill and flowers

*This post may contain affiliate links. As an Amazon Associate we earn from qualifying purchases.

If you are looking at saving on heating or air conditioning in your home, energy efficient windows may be the answer, but are they all they’re cracked up to be?

What is an Energy Efficient Window

If your home has a draft or if your heating and air conditioning bills are through the roof, it may be that up to 1/3 of your home’s air is literally flying out the windows, especially if you have an older home with its original windows.

The term “energy efficient window” is a little confusing because there are no specific definitions. When most people think of energy efficient windows, they generally think of brand-new, high-priced double-paned windows. While that is true, there are also steps you can make without replacing your windows, and you might even see dramatic improvements on your utility bills.

Window efficiency measurement is by U-factor, which is the rate of heat loss. Most windows fall between .20 and 1.20 — the lower the number the better. The U-factor isn’t the only way to measure energy efficient windows, though. You want your windows to proved protection from the sun. The solar heat gain coefficient (SHGC) measures how well your windows absorb the sun’s radiation, which can bleach your furniture and flooring and even damage your skin. SHGC is measured between 0 and 1; again, lower is better.

To maximize energy efficiency, opt for double, or even triple-paned windows. The more, the better. The glass isn’t the only place you’re losing energy, though. If your window frames are old and not well sealed, you are losing heat and cool.


Types of Energy Efficient Windows

Naturally, energy efficient windows come in all shapes and sizes, but they also come in several different materials. The most popular frame materials for energy efficient windows are vinyl and aluminum, but you can still find wood windows — for a price.


For many, vinyl windows are the gold-standard. They are virtually no-maintenance, but there are trade-offs. Vinyl windows need no painting. Since vinyl windows are dyed and not painted, if they are scratched or chipped, they still retain their color. Vinyl windows age almost seamlessly, with no maintenance. There is no corrosion, fading or pitting.

Vinyl windows offer a tight seal, with almost no condensation. They offer the best efficiency as well as the best noise reductions.

The downside of vinyl windows is that they can’t be repainted, so if you decide to change your home’s colors, you will have to choose paint around your window colors.

As for looks, vinyl does a great job of mimicking wood. Vinyl windows offer thick frames and in styles that can match your home’s exterior.


Aluminum windows can be less expensive than vinyl windows, and they can be painted, but they come with some serious downsides. Unless you are willing to shell out a lot of money, aluminum windows are far less energy efficient than vinyl.

Metal frames are thinner than aluminum, which often looks cheaper. They are also prone to chips and scratches, and since they are not dyed like vinyl, the metal will show through. They will also fade.

The metal fasteners on aluminum windows are susceptible to corrosion. Aluminum windows retain heat very well, which is great in the winter, but not so much during the summer. Aluminum frames are less efficient at eliminating condensation; they invite mildew, mold and general rot. Some offer vinyl thermal breaks to offset the condensation problem.

On the upside, aluminum windows are a bit stronger than vinyl. You can repaint them. You can get the best match to your home’s colors if you use a powder coat paint.


If you prefer a perfect match for your home’s exterior and you want the flexibility of painting and repainting, you might opt for wood. Wood comes with a lot of familiar problems, though. Wood requires a lot of maintenance and can easily chip and scratch. It is porous, which means that it can’t be as energy efficient as vinyl. Wood is also considerably more expensive than other materials.


One compromise is composite windows, which offer stability you won’t find in regular wood windows. Composite frames are made of wood particles put together with a sealant, much like particle board, making them stronger and more resilient than standard wood.

While composite windows are quite durable, they can’t match up to vinyl, especially in tough weather conditions. Because they are made from a variety of materials, you never know quite what you are going to get until it’s installed.


Fiberglass windows are three times more efficient than even vinyl windows because they don’t expand or contract with the temperatures and they can be insulated. The colors on fiberglass windows can fade, but unlike vinyl, they can be repainted. Some even have wood coverings.

Fiberglass is relatively new to the market, so it can be difficult to find and you can’t get them on a moment’s notice. They’re also more expensive than vinyl.

How Much Money Can Energy Efficient Windows Save


On average, you will save about 12%-33% of your total heating bill. On average, that’s an annual savings of about $100 to $300. The more windows you have, the more you will save.

Do Energy Efficient Windows Increase Property Values?

While the annual savings may not be that impressive, on an average home, new windows will add about 74 percent of your investment to the home’s value. In other words, if you spend $15,000 on new windows, they will add about $11,000 to your home’s value.

Does Your House Have Energy Efficient Windows?

Sometimes it’s easy to tell if your home has energy efficient windows, and sometimes, not so much. Touch the inside of your windows on a cold or a hot day. If they are closer to the outside temperature than the inside temperature, odds are, you have old, single-paned windows.

You can also look at the frames. If they have old wood, they are likely not energy efficient. If they have thin, corroded aluminum, again, not energy efficient.

How Much Does Window Replacement Cost

The cost of energy efficient windows are as varied as houses. You could spend anywhere from around $270 per window to more than $800. If your windows are large, expect to spend in the higher range.

Are There Tax Credits for Energy Efficient Windows?

Tax credits for energy efficient windows are relatively minimal. You can expect to save about $200.

How Do You Find a Reliable Window Installation Contractor

A bad window contractor can be a ripoff, dangerous and can even damage your energy efficiency. Do your due diligence. Find out if the installer is certified. It’s even better to find a contractor who was directly trained by the manufacturer. Check reviews on Yelp, the Better Busienss Bureau and Angie’s List. Check references.

Ask about warranties. There’s nothing worse than a boarded up house, so ask how long installation will take.

Get several estimates. Ask about labor costs and materials costs and compare those figures instead of just the total.

Where to Buy Windows

It is possible to install your own windows at a significant savings, if they are done right. Even if you choose to use a contractor for installation, you can still save money by ordering windows yourself. Otherwise, you may feel roped into using the installer’s preferred manufacturer and materials.

You can find widows at home improvement stores and even sometimes, at contractor resale stores, especially if your windows are a fairly standard size. Windows can be very difficult to install, though.

Are there Downsides to Window Replacement?

The vast majority of homeowners are happy with their replacement windows, but there are some downsides. The most evident is the cost. It can take decades to recoup if you stay in your home. With most materials, you lose some ability to repaint, meaning you’re stuck with the same trim color forever.

Cheap Alternatives to Window Replacement


Unless you have a cosmetic reason for replacing your windows, you might try some other alternatives.

Window inserts

A window insert is a magnetic or snap fitting that goes outside the window. It essentially turns a single-paned window into a double-paned. On average, the cost is from $24 to over $100 per square foot. You can expect to save at least 50 percent over new windows.

Indow inserts

No, that’s not a typo. Indow inserts are similar to window inserts in that they snap in, but they are installed inside instead of outside. The cost is similar to window inserts.


If your home is more than a few years old, there’s a good chance you need new caulking around your windows. Remove all the old caulk with a putty knife, then fill in the gaps. It’s best to wait for a few rain-free days before attempting it, to give the caulk some time to dry and to give you time to finish the job.

New window treatments

Sometimes, the best alternative to new windows is what covers them. A good insulating window treatment can save you a lot of money and add beauty to the interior of your home. Cellular or pleated shades offer extra insulation, but any lined curtain will help your home retain its ambient temperature. For more information on easy cost-saving measures, the US Department of Energy has some great resources.

Featured image CC by 0, via Pixabay

Recent Posts