How to Insulate Windows (2023 Homeowner’s Guide)
By Dan Simms /
In this guide on different types of windows, you’ll learn:
If you are wondering what type of window is right for your home or are curious about their cost and energy efficiency, this guide will help you obtain all the necessary information to make the right window choice. Enter you zip code below to get a personalized quote on window options near you.
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When it comes to choosing a window to install in your home, you have far more options than you might think. There are 23 different styles, all with varying functionality, aesthetics and, most importantly, levels of energy efficiency. Below, we’ll be explaining the differences between every window style, discussing the pros and cons of each and providing some insight into which are the most energy efficient.
|Casement Windows||Garden Windows|
|Transom Windows||Bow Windows|
|Awning Windows||Arched Windows|
|Storm Windows||Hopper Windows|
|Bay Windows||Skylight Windows|
|Glass Bock Windows||Round or Circle Windows|
|Jalousie Windows||Oriel Windows|
|Double-Hung Windows||Cottage Windows|
|Single-Hung Windows||Three-Panel Slider Windows|
|Picture Windows||Other Shapes|
|Sliding Windows||Special and Custom Windows|
You’ll often see casement windows as a component of bay windows, but they can stand on their own as well. This type of window has hinges on one side, and the other side pivots out, away from your home’s exterior. Casement windows usually open and close using a crank located on the inside of the window.
The average cost to install a casement window is around $725. You could purchase an average casement window for around $450 if you plan to do the installation yourself as a DIY home improvement project.
Casement windows are the most energy-efficient style among windows that open because the sash isn’t meant to slide freely in the window frame. Because of this, a tighter seal using compression is possible.
A transom window, sometimes called a lunette window, is the kind you typically see above exterior doors. They sit high enough to maintain privacy while allowing sunlight in, but they do not open.
The average cost to install a transom window varies quite a lot based on the quality, size, and shape of the window you need. They can range from around $200 up to over $1,750 in some cases such as curved options like fanlights.
Transom windows are highly energy efficient because they don’t open. They provide natural light in your home without the limited efficiency of a breakable seal.
An awning window is typically wider than it is tall. It is hinged on the top and opens outward, creating an awning effect to protect your home’s interior from rain. Awning windows are more popular for below-grade basements, but they can be found in other areas of the home as well.
You can expect to pay around $600 to $700 for a new awning window installation, depending on the size and location.
Like casement windows, awning windows create a tight compression seal when closed to provide the benefit of an openable window with maximum energy efficiency.
A storm window or hurricane impact window is installed over a regular window. It can be made of tempered glass or fiberglass, and it provides protection from extreme weather. It’s more affordable to replace a storm window than the one it’s meant to shield. Storm windows also increase your home’s energy efficiency, so they’re a great option to maximize safety and reduce your carbon footprint.
Storm windows are very affordable and usually average around $150 each. They can save you from spending multiple hundreds of dollars on the windows they protect and save you money on your energy bills.
Storm windows aren’t particularly energy efficient on their own (if your regular windows are open). However, when your regular windows are closed they add to your home’s energy efficiency by providing another pane that insulates your windows and home.
A bay window consists of three different surfaces — two that extend out from your exterior wall at an angle, and one that sits between the other two parallel to the wall. Bay windows add beauty and elegance to your home’s interior and exterior, and they can make your interior space feel much larger. They also provide plenty of natural sunlight.
The major downside of bay windows is the cost. In general, you can expect to pay around $2,200 to install one, on average, or anywhere from $750 to $5,000, depending on the size and location.
The different surfaces of bay windows can be configured to open completely or partially and have one or several panes. Those that open aren’t as energy efficient as those that don’t. Opening bay windows with casement-style panes are more energy-efficient than those with single-hung or double-hung windows. Given the large size of the glass panes, bay windows are among the least energy-efficient styles that open.
Glass block windows consist of thick cubes of glass that often have a frosting on them to provide privacy. They’re decorative in nature, so they don’t open or provide fresh air. They do allow some sunlight in, and their thickness makes them the most energy-efficient fixed window style.
Glass block windows are a bit on the expensive side, at an average of around $750. The size of the window and the number of blocks you want can bring this price up or down significantly.
Glass block windows are exceptionally thick, and they don’t open to allow ventilation. As such, they are the best windows for energy efficiency.
Jalousie windows are quite rare in America. They act like blinds in that they have multiple horizontal panes of glass that tilt to open and close. These windows are among the most affordable but are the least energy-efficient of all window types.
Jalousie windows are very affordable, averaging around $350 each for the materials and installation. However, you might have difficulty finding them, as they are quite rare.
Jalousie windows have multiple panes that seal against each other. As the seals are intrinsically loose, jalousies are the least energy-efficient windows out there.
A double-hung window is the most common type of window in America. It consists of two sashes — a top and bottom sash — that slide up and down in the window frame for ventilation and can extend outward to make cleaning easier. These windows are affordable, but they aren’t the most energy-efficient because of the sliding sashes.
Double-hung windows cost around $450 to replace, making them one of the more affordable options. They also come in a massive variety of sizes, making it easy to find new windows or replacement windows.
Modern double-hung windows are relatively energy-efficient, but they lose some efficiency because the sashes need to slide and can’t be sealed too tightly.
A single-hung window is very similar to a double-hung window, but it only has one movable sash; the other sash is fixed. The moving sash slides up and down in the frame to provide ventilation.
Single-hung windows are some of the most affordable window options available. The average cost to install one is around $300 for the labor and the materials.
Single-hung windows are more energy-efficient than double-hung windows because of the upper sash that is fixed and permanently sealed. However, they still aren’t as efficient as casement windows because the bottom sash needs to slide and the seal can’t be as tight.
A picture window is the simplest kind of fixed window. It looks similar to a double-hung or single-hung window, but there are no movable sashes. Picture windows are more energy-efficient than all moving windows, but they don’t provide any ventilation.
A picture window typically costs around $350 to install, making them very affordable options where you don’t need ventilation.
Picture windows are fixed and have no movable sashes so they are more energy-efficient than all openable windows.
Sliding windows are just what they sound like: they have sashes that run from the top to bottom of the window frame and slide left to right to provide ventilation. Most sliding windows have two panes that slide independently of each other.
Sliding windows average around $500 to install, making them moderately expensive. Larger sliding windows can increase significantly in price.
Sliding windows are not very energy efficient. Not only do they have sliding sashes that reduce efficiency along the tops and bottoms of the sashes, but the individual sashes can only seal with each other where they meet, creating a weaker seal than with the frame.
Egress windows are designed for basements that sit underground and would otherwise only be suitable for smaller window options. These windows open out into a small egress outside of your basement wall. They provide more sunlight than most other basement windows, as well as the opportunity to exit the basement in case of an emergency.
Egress windows cost around $4,000 to install. The cost is so high because they are installed in your foundation wall, which might require reinforcing in some areas and getting through the concrete to install the window frame. The excavation outside of your window can also add to the cost.
Egress windows can open in a variety of ways, and the energy efficiency depends somewhat on how your window opens. For example, casement egress windows are more energy-efficient than double-hung egress windows. None are as energy-efficient as fixed windows, though.
A garden window is a glass box that bumps out from your exterior wall, often over your kitchen sink. As the name suggests, it’s typically used to house plants, as the entire window acts as a small greenhouse. Garden windows typically don’t open, so they’re exclusively for sunlight and growing plants.
Garden windows are very expensive, averaging around $2,500 for a professional installation. Larger garden windows will naturally be more costly.
These types of windows are fixed, so they are quite energy efficient. They aren’t as efficient as flat fixed windows like picture windows because they have more glass that transmits heat and cold, but they are more efficient than all opening windows.
A bow window is similar to a bay window in that it’s large and protrudes from your exterior wall. Rather than having three panes like a bay window, a bow window has many smaller panes that bow out in a smooth semicircle.
Bow windows are expensive, averaging around $5,000 to buy and install. Larger options or those with more panes can top $7,500 in some cases.
Bow windows don’t open, so they’re more energy-efficient than styles that do. Given how much glass is exposed to the elements, though, they aren’t as efficient as other fixed options.
An arched window is just a picture window with an arched top. These windows don’t open, making them a great energy-efficient option to add sunlight to your home’s interior.
Arched windows are more challenging to make and install than rectangular picture windows, so they naturally cost more. The average arched window will cost you around $400.
Arched windows have no moving sashes, so they are pretty energy efficient. The only styles that provide more energy efficiency are glass block windows or another smaller fixed window option.
A hopper window is traditionally used for below-grade basements. They are similar to awning windows in that they’re hinged at the top, but they open inward. These windows offer sunlight where it is often scarce, and they don’t protrude into your yard when they’re opened.
Hopper windows are quite small and expensive for the size but affordable based on the price — around $400 each.
Hopper windows are more energy-efficient than styles with sliding sashes, but they aren’t quite as efficient as fixed windows.
Skylight windows are installed in your roof, so they provide natural sunlight from above for your living spaces. Some open and are a bit less energy efficient than the ones that are fixed. Unfortunately, skylight windows are the most likely of all the window types to leak, given that they are situated horizontally.
Skylight windows cost around $1,000 to install, and a professional installation is required to limit the risk of leaking.
Skylight windows can open or remain fixed. Those that are fixed are as efficient as picture or arched windows. Those that open are about as efficient as casement windows, which is the most efficient style of opening window.
A round, or circle, window is a fixed window that is purely for aesthetics. It’s perfectly circular and can be installed on any exterior wall. Installation costs are high because it can be challenging to frame a round window.
You can expect a round window to cost you around $800 to $1,000 to install, given the difficulty of framing this type of window.
Circle windows are highly energy-efficient and will reduce heat transfer about as much as any other equal-sized fixed window. However, they tend to be smaller than other styles, so they’re often more energy-efficient than picture windows.
Oriel windows look very similar to bay windows but are typically located on upper stories. Given the location, they are supported by corbels or similar supports. Oriel windows can have a variety of opening mechanisms or be fully fixed.
Oriel windows are heavy, which makes them challenging to install on upper stories. You can expect to pay around $1,500 to install one.
Fixed oriel windows have more glass exposed to the exterior than picture windows, meaning they are less energy efficient. However, they are more efficient than opening styles. Oriel windows that open are not as energy efficient as fixed versions.
A cottage window is just a single-hung window, but the upper, fixed window sash is much shorter than the lower one that opens.
Cottage windows are about the same price as a double-hung window, averaging around $475. They are less common than other styles and can be more challenging to find.
Cottage windows are just slightly less energy efficient than single-hung windows, as the longer lower sash has a longer side that slides and creates an imperfect seal. They are also less energy efficient than all fixed windows.
Three-panel slider windows are just like sliding windows mentioned above, but they have three movable panes rather than two. They add a unique look to your home and allow for more ventilation than traditional sliding options.
Three-panel sliders are more costly than other types of sliding windows, as they are more complex and often larger. You will pay around $800 for a three-panel slider.
Three-panel sliders are among the least energy-efficient windows. Each sliding sash creates an imperfect seal with the one next to it, and each also has an imperfect seal with the frame around it.
Windows come in all different shapes and sizes. You can find other types of windows that are triangular, hexagonal, or pentagonal, or windows with unique bows and curves, like a swept-sash window or a semicircular window. Unique shapes will generally cost more than standard ones, but they add a decorative look to your home that can be very striking.
Windows of different shapes can range significantly in price, from around $300 to upwards of $2,000. The price depends largely on the size of the window and how challenging it is to frame it.
Uniquely shaped windows are almost always fixed, which means they will tend to be more energy-efficient than all openable windows. The smaller the window, the more energy-efficient it will be, regardless of the shape.
Finally, you can also buy specialty or custom windows to fit a particular need or your home style. Specialty windows can be just about any shape or size, but the cost is immense compared to standard options.
Specialty and custom windows tend to start around $1,000 for very small windows and can climb to well over $7,500, depending on the size and shape.
Every custom window is different, so it’s impossible to say how energy efficient yours will be. Those that open will be less energy efficient than fixed options.
With increasing concerns about carbon footprints, many homeowners are wondering about the efficiency of different types of windows. By choosing a window with a high efficiency rating, you can minimize your heating and cooling bills, make your home more comfortable, and reduce your contribution to global warming.
Fixed windows — those that don’t open — will always be more energy efficient than openable window styles. By their nature, moving sashes have imperfect seals that allow for some heat transfer. Sashes that slide are less efficient than those that pivot, making casement windows the most efficient opening style. Additionally, the smaller the window, the less heat transfer will take place through the glass, and the more energy efficient your window will be.
The type of glass matters as well. Single-glazed windows are the least energy efficient but also the most affordable. Double-glazed windows add another layer of glass and an insulating gas — usually argon or krypton — sealed between the panes to improve efficiency. Triple-glazed windows have three panes of glass and two layers of gas for maximum efficiency.
Lastly, the frame material matters. Fiberglass and wood windows are among the most efficient, while vinyl windows are more affordable but also well-insulating.
Below are the top five most energy-efficient window types:
Double-hung windows are, by far, the most common style in America. They’re affordable, easy to clean, and offer sunlight and ventilation. Other common styles include single-hung windows, casement windows, and picture windows.
The size of the window is a major cost factor, with larger windows requiring more material and being more challenging to install. The location of the window also matters, as windows on the second floor are naturally more dangerous and difficult to install. The quality of the glass (single-, double- or triple-glazed) is a huge cost factor as well, with more efficiency costing more. The functionality of the window is a minor cost factor, with openable windows costing more than fixed options.
All fixed windows are airtight, as they have no seams exposed to the elements. These include glass block windows, picture windows, circle windows and transom windows. Of the opening window styles, casement windows, awning windows and hopper windows are the most airtight but do allow some air to seep through the seams.