Who doesn’t love a generously sized window looking out over a beautiful sunset or forest scene? Projection windows — more commonly known as “bay windows” or “bow windows” — are a staple of residential architecture because they maximize awe-inspiring views and reliably provide natural light indoors.

Adding or upgrading a projection window to a room in your home is an excellent way to elevate a simple space into something extraordinary. But whether you need to replace an existing window or you’re in the market to add one to your home, deciding between a bay or a bow window is an essential step in the process. 


At first glance, these two window styles may seem similar. Both extend beyond the house’s exterior wall, and both provide ample natural light to a room. And, when you choose the right energy-efficient window, both can save you a lot of money on your energy costs. 

But that’s about where the similarities end. Bay windows and bow windows aren’t interchangeable. It’s crucial to understand the difference between these choices and how they can benefit a home’s look and function before deciding. 

Ease of Operation: How They Work

Bay and bow windows may look similar if you’re standing on the curb looking at a house. But these windows have some marked differences that can impact which one you choose when shopping for replacement windows. 

Bay Windows

What is a bay window? A bay window is a combination of three windows that angle away from the home’s exterior wall. They usually consist of one large picture window framed by two smaller windows — typically double-hung or casement windows. Depending on your home’s architecture, you can have bay windows installed at up to a 90-degree angle, providing extended exterior views and sometimes even more interior seating. Who doesn’t want a sunny window seat where they can curl up with a cup of hot coffee and a good book? And, if you opt to forgo the window seat, a bay window can create additional square footage in your home. In times like these, we can all use a few extra feet of space wherever we can find it! 

Bow Windows

What is a bow window? Like bay windows, bow windows extend beyond your home’s exterior wall. However, these windows are very different. Bow windows consist of anywhere from four to six windows aligned in a graceful arc, rather than a bay window’s boxy corners. Because bow windows have more glass and fewer corners, they are typically larger and let in even more light. Bow windows are an excellent way to make any room seem brighter and bigger. They also provide ample space to add a window seat with storage underneath. How’s that for form and function? 

Look and Location

The best way to remember which window is which is to remember that a bow window is rounded, like a bow on a package or a wreath. A bay window is more square, like a cargo bay or box would be. Where are you more likely to find each of these windows? 

Bay Windows

Bay windows come in various shapes and styles, so there are options for homes with all different designs. You’ll often find bay windows in houses with more contemporary designs because their angular look complements modern architecture. Bay windows are available in square, hexagonal or octagonal designs. They’re also a smart choice if you’re looking to add square footage to a room in your home. 

One thing to remember about bay windows is that they project a bit. If your house is close to the sidewalk or you’re having the window installed on a side of your house that faces a neighbor or a driveway, be sure to measure your available space to ensure there’s plenty of room for a bay window. There’s nothing worse than rounding a corner and running straight into a window! 

While the center window in a bay window typically doesn’t open, the side windows can open for ventilation. That means when those mild spring and fall temperatures arrive, your beautiful window does more than let in sunlight — it allows you to enjoy fresh air, too.

Bow Windows

Many people love bow windows’ graceful look because they don’t have the sharp angles you find on a bay window. These elegant windows complement formal living rooms, master bedrooms and even a breakfast nook or dining room. You might expect to see them in homes with older architecture. They’re a well-known feature of Victorian houses. They also complement homes situated on a property with beautiful views, making them an excellent addition to a room facing water, trees or mountains — whatever vista is outside your home. 

The panoramic views are possible without protruding from the house as far as a bay window. This narrower exterior profile makes bow windows an ideal option for homes that don’t have a lot of extra space outdoors and need something that won’t extend into the sidewalk or street. 

Because the windows are so close together, bow windows do not open for ventilation. Their primary purpose is decorative, and you should have them installed in a room with ample ventilation available.  


While cost shouldn’t be the only thing you consider when purchasing new windows, we know it’s at the top of your priority list. Window replacement can be an expensive undertaking, but that’s because it can be such a valuable investment. And choosing the right windows now will save you money in the long run. How? Besides reducing your monthly energy costs, high-quality, energy-efficient windows can yield as much as a 78% return on investment when you sell your house later on. 

Window costs can vary significantly, depending on their material and energy efficiency. Labor costs also vary from one location to another, as do additional fees, depending on whether you’re replacing an existing bow or bay window or having a new one constructed.

Bay Windows

Bay window costs largely depend on whether you are replacing an existing bay window. If so, your costs will be much lower. On average, a vinyl bay window will cost around $2,600. However, if you’re creating a bay window to gain square footage and a window seat, you can also expect to pay for the minor construction work necessary to make a bump-out alcove, window seat and other add-ons. Unless the bay window happens to sit under your home’s eaves, you may also have to pay to have a small roof constructed over the top of it. 

Bow Windows

At first glance, bow windows may seem more expensive. That’s because bow windows typically have four or five windows, so you’re paying for additional windows that you don’t have on a bay. However, bow window installation doesn’t typically require as much construction as a new bay window unless you opt to construct a bump-out alcove. In that case, you’ll also be paying for flooring, drywall and other minor construction costs. To get a more accurate picture of bow window cost, it’s smart to consult with an experienced window installation company

Natural Light

One of the advantages you’ll enjoy with both of these windows is that they let in a lot of natural light. But does one win out over the other? 

Bay Windows

Bay windows provide more natural light than a traditional flat window will. Besides brightening up space in a room, a bay window that also comes with extra square footage lets in ample natural light for reading, painting or soaking up the sunshine. 

Bow Windows

While bay windows offer more natural light than a standard window, their design blocks some of the available natural light. In contrast, bow windows are an excellent way to get the maximum amount of natural light in nearly any space. Besides allowing more natural light to flow into your home, they provide a broader view of the outdoors, complementing the surrounding scenery that attracted you to your home in the first place! 

Energy Efficiency

These days, you can’t research new windows without encountering the term “energy efficiency,” but what does it mean, and which window gives you more bang for your buck? It’s true that larger windows tend to be less efficient than smaller ones, but does that mean you should shy away from them all? 

No! Today’s bay and bow windows can provide you with maximum efficiency. And if you’re upgrading from an older bay or bow window, you’ll see energy savings with a newer model. But is one better than the other? 

Bay Windows

Since bay windows tend to be slightly smaller than a bow window, they may offer a bit more energy efficiency. However, their efficiency level still largely depends on the glass quality and the installer’s ability to place and seal the window correctly. 

Bow Windows

Bow windows are typically larger than bay windows, which means there is more glass in them and more of an opportunity for heat to transfer through the glass. That’s why it’s essential to choose glass with sufficient low-E coating. Low-E glass can maximize your home’s energy efficiency by keeping the heat inside and preventing most of it from slipping through the glass. In other words, if you have your heart set on a bow window, it’s vital to choose windows whose design allows for maximum efficiency. 


Picture this: It’s a warm spring day. There’s a hint of a breeze, and birds are chirping. You throw open your windows, sit down on the couch and enjoy the sun’s rays warming your skin. It’s one of life’s simple pleasures to open your windows when the weather allows. But what options do bay and bow windows offer to enjoy delightful weather? 

Bay Windows

Bay windows consist of a picture window in the center, framed by two standard double-hung or casement windows. The windows on the sides can open to take advantage of warm breezes and mild temperatures. They can bring natural light and fresh air to any room.

Bow Windows

While it’s possible to install bow windows that open, we usually discourage it. Because a bow window consists of several windows placed close together, there’s not enough room to easily incorporate a mechanism to open them. If you have your heart set on a bow window, consider putting it in a room that already has several other standard windows. You can then benefit from the ventilation of standard double-hung or casement windows with the natural light and beautiful views a bow window provides. 


Bay windows and bow windows provide a stunning feature for nearly any room in your home. So, how do you keep these generously sized windows sparkling clean? 

Bay Windows

If your bay window incorporates traditional double-hung windows, these will be easy to clean, since you can open them and angle them inward for thorough cleaning inside and out. Depending on your bay window’s size, you may want to invest in a small squeegee to ensure that you thoroughly clean the entire surface area. Cleaning a bay window’s exterior will require going outside and standing on a stepstool or small ladder, depending on the window’s location. If you need to use a ladder or stepstool, always take the necessary safety precautions to ensure you don’t fall. Never do this while you’re home alone. Have another adult standing at the bottom of the ladder to ensure that it stays steady while you clean.

Bow Windows

To clean the inside of a bow window, spray glass cleaner on each section and then wipe with a cloth or small squeegee, depending on the size of the glass. Since bow windows typically do not open, you’ll need to clean the exterior by going outside and using a stepstool or ladder to reach the window. As we said before, never use a ladder to wash windows when you are home alone, and always have another adult nearby to ensure that the ladder stays steady while you work.  

Window Installation: Call Your Local Glass Experts

If you need to replace a bow or bay window, now is an excellent time to upgrade to an energy-efficient window designed to reduce your energy costs and maximize your home’s natural lighting and curb appeal.

At Garrety Glass, our experienced team is available to help you choose the best window for your home. But we don’t stop there. Our in-house installation team has the knowledge and experience necessary to install your windows correctly and provide you with beauty and comfort you can enjoy for years to come. 

Contact us today for a free quote.