Key Takeaways
- Bay windows are an exterior bump-out constructed of three windows. They can add interest, natural light, and built-in seating.
- Most bay windows range in width from 3 to 10 feet and in height from 3 to 6 feet.
- Bay window costs range from $750 to $4,000 on average.
If you’re looking to add more natural light, architectural interest, panoramic views, or even built-in seating to your home, a bay window might be the perfect upgrade. This exterior-protruding window set features a central window flanked by two side windows — usually installed at a 30-, 45-, or 90-degree angle to form an alcove.
Bay windows come in a wide range of sizes, but most fall between 3 and 10 feet wide and 3 and 6 feet tall. Depths usually range from 1 to 2 feet, depending on how dramatic or functional you want the bump-out to be.
“Consider the goals for your space,” said Chris Hurd, senior director of group product management at Marvin. Hurd added that how you intend to use the space will help you determine the appropriate scale and depth of the new window.
You’ll also need to consider your home’s existing construction and architectural style when selecting the right window size. Due to the wide range of sizes, materials, and add-ons, bay window prices vary accordingly.
Read on to learn which factors influence costs and where you should install your new bay window. We’ll help you determine whether you can install a bay window on your own or whether it makes sense to hire a professional window installer.
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How To Choose a Bay Window Size
First, it’s important to know what your home’s structure can support, what your intended function for the window is, and how much natural light you want.
Most residential bay windows range in width from 3 to 10 feet and in height from 3 to 6 feet. Standard bay window depth ranges from 1 to 2 feet, but you can go deeper if your structure allows. Deeper bays give you more usable space for seating or display but require more support and framing adjustments.
Most prebuilt bay windows come in standard 3-panel setups, with 3-foot-wide angled side windows and a 4-foot-wide center window. Custom builds are pricier but allow you to tailor dimensions to your wall and room layout.
You should also evaluate how the new window will impact your home’s exterior. “For a more cohesive look when adding new windows, determine how a new opening will measure against existing windows and doors to ensure balance,” Hurd said. “I recommend consulting with a builder or local expert to explore the best avenue for bringing your bay window to life in a size and shape that meets your family’s needs.”
How To Measure
The width is measured across the front, from the outside edges of each side window. For example, if each side window is 3 feet wide, and the center window is 4 feet wide, you’d have a 10-foot-wide bay window.
When measuring height, measure from the sill to the top of the frame, and when measuring depth, measure from the wall to the furthest point of the bay window’s frame.
Where To Use Bay Windows
Bay windows can suit many architectural styles. “Homeowners may have a preconception about the architectural styles that work best with bay windows — historically, they’ve been associated with a more traditional home,” Hurd said. However, that’s no longer the case, as modern materials and designs, such as the box bay window trend, make adding a bay window to any home style a seamless and intentional addition.
Bay windows look great in common gathering spaces, such as kitchens or living rooms. With larger bay windows, you can create a cozy nook in these high-traffic areas that is an intimate space for introspection without feeling far removed from the action.
However, as Hurd pointed out, adding a bay window to an otherwise small or underutilized space, such as a hallway, stair landing, or office, is a unique addition that can bring in light and airiness. Adding just that small amount of square footage can transform a utilitarian area into something much more.
How Much Do Bay Windows Cost?
The main factor affecting bay window cost is size, but other factors play a role too — such as whether it’s fixed or operable, as well as its energy-efficiency rating, frame material, and shape.
The table below shows prices for various bay window sizes:
| Bay Window Dimensions | Cost per Window |
|---|---|
| 4’ x 3’ | $750–$1,850 |
| 6’ x 3’ | $850–$2,900 |
| 8’ x 3’ | $900–$3,250 |
| 10’ x 3’ | $850–$4,000 |
Expect to pay about 25% more at minimum for energy-efficient windows, and keep in mind that window treatments are difficult to install on bay windows. If you live in a region with extreme climate conditions, it may be worthwhile to invest in thermal upgrades.
DIY Vs. Pro Installation
Bay windows are an important structural component of your home, and their installation should not be taken lightly. While experienced homeowners may be able to replace an existing bay window of the same size in an already-framed opening, adding a new bay window is not a recommended DIY project.
Bay windows and other complex window assemblies, such as bow windows, require a technical installation and often necessitate additional construction, including support framing, widening, or narrowing an opening.
Bar Zakheim, CEO of Better Place Design & Build in San Diego, said he wouldn’t risk it. “Bay windows are not for beginning DIYers. Because you have to modify your home’s exterior, there’s a big risk of mistakes that could lead to long-term water damage. I would definitely call in a professional for this kind of work.”
Hurd agreed and said he always recommends working with a skilled and experienced installer when replacing windows.
Your best bet is to gather a few bids and speak with your installer directly about what works best for your home.
Bay Vs. Bow Windows
It’s important to note that bay windows and bow windows are two entirely different things, with the main distinction being the number of windows each has in its construction. Here’s a quick look at the differences:
- Bay windows consist of three windows and sharp angles, whereas bow windows consist of four or more windows arranged in a gentle curve.
- Bay windows offer a more dramatic architectural style, while bow windows have a more elegant appearance.
- Bow windows cost more due to their complex structure and the additional windows they require.
- Installation costs for bow windows are also higher due to the need for more skilled labor during the installation process.
- Both styles offer an abundance of natural light, but bow window panels are often smaller, which can make ventilation more challenging.
Are Bay Windows Right for You?
Bay windows are a fantastic addition to any home, offering architectural interest, additional square footage, ventilation, and natural light.
A good installer will listen to your needs and outline your options to help you choose the best fit for your home, inside and out. Replacing a bay window will cost less than adding one, but if you decide to make this rewarding upgrade to your home, be sure to account for labor costs, any structural upgrades needed, and the costs to reconfigure your home’s siding surrounding your new window.
Hurd recommends exploring your options. “Find inspiration on social media or in magazines, take stock of styles and products you connect with, or seek out a trusted local window dealer to discuss possibilities.”
