Arched Window Guide

What Are Arched Windows?

Arched windows, also known as half-moon windows (among other names), are exactly what they sound like: A window that has an arched shape at the top. These windows can help a room feel brighter and more open. Their rounded top lets in more natural light, not to mention their architectural appeal unique. Arched windows were used heavily in Roman architecture and are now used in modern homes for their timeless appeal.

Arched Window Options

There are two ways to approach the design of your arched window:

1. Single Window Configuration: The arch is manufactured into the design.
2. Multi-Window Configuration: You’ll have a transom arch above a standard rectangular window.

Here are the advantages and drawbacks of both.

Types of Arched Windows

Arched windows are known by many names. Not everyone uses the same terms the same way.

For example, one installer might use “curved window” to describe a single window unit manufactured with an arched top. Another might use the same term to mean a standard rectangular window paired with an arched transom above it.

Always ask contractors exactly what type of arched window they mean when they use a term like “radius,” “curved,” or “arched top.” Clear communication upfront avoids surprises later.

You may hear or read about any of the following terms, all of which mean an arched window:

• Arched top windows or rounded top windows.
• Radius windows.
• Domed windows.
• Half-moon windows.
• Semi-circle or half-circle windows.
• Curved window.

Looking for an arched window that has a window on either side of it like in the photo above? Then you want a Palladian window.

What Does a Curved Window Cost?

The national average cost for arched windows is $345 to $950. Depending on your window’s size, the project cost may be as high as $3,000. You can check out our guide to arched window prices to learn more about what’s involved in that cost range.

Half-Moon Windows: An Exception to the Rule?

Most arched window terms are used interchangeably, but a few tend to refer more specifically to arched transom windows: the curved glass portion that sits above a standard rectangular window or door.

Use These Terms When Replacing Just the Arch

If you’re replacing only the arched portion, especially in a multi-window setup, use terms like:

• Half-moon window
• Semi-circle window
• Half-circle window

These terms are especially relevant if:

• The window is above your front door
• You have a multi-window configuration and only the arched transom is damaged

Use These Terms When Replacing the Whole Unit

If you’re replacing both the arched transom and the rectangular window below it, then the following terms are more appropriate:

• Arched top window
• Curved window
• Radius window

These describe the entire arched window unit, not just the curved transom on top.

Can Arched Top Windows Open?

They can, yes! The most popular styles of operable arched windows are:

• Casement.
• Awning.
• Single-hung.
• Double-hung.

Be aware that casement windows and smaller awning windows can be manufactured as a single window unit. Single-hung and double-hung arched windows can also be created as a single window, but the moving sash will only come up in the rectangular part of the window.

Or, like in the picture above, you can choose a standard rectangular window that opens and add a transom arch on top to create the curved shape.

Windows With Arches: Next Steps

Now that you have a better idea of all the choices that come along with an arched window replacement, it’s time to find a trustworthy window installer near you.

Start by getting quotes for an arched window. You can do that by exploring our window contractor directory to compare the pros in your area. Or, Modernize can do the research for you. We can match you with up to four pros, which will help you find the best price as well as a trusted contractor.