Standard Double Hung Window Sizes (with Drawings)

Stacy Randall
by Stacy Randall

Replacing your windows is one of the best ways to increase your home’s value and improve its efficiency. A common window style in the US is a double-hung window. Although you can splurge on custom sizes, standard double-hung window sizes keep things much more affordable.

Standard double-hung windows range from 24 to 48 inches wide, with heights between 36 and 72 inches. Available standard size widths are 24, 28, 32, 40, 44, and 48 inches. The available standard heights for double-hung windows are 36, 44, 48, 52, 54, 60, 62, and 72 inches. But the actual size is ½ inch less than these measurements.

Replacing standard-size double-hung windows is an easy way to add instant value to your home. If you’re about to go window shopping, make sure you understand how windows sizes work.


Deciphering Standard Window Sizes

When you purchase new or replacement windows, it’s important to know how to correctly read the dimensions. Windows aren’t always marked with measurements like 24” x 36” or 28” x 54”. So how do you know you’re getting the right size?

You need to understand how manufacturers label window sizes. They do it with four-digit numbers called size notions or call sizes. The first two digits represent the width, and the last two digits represent the height.

Within each pair of digits, you can determine the feet and inches. For example, if a window is 24” by 36”, the four-digit identifier would be 2030.

The two stands for two feet wide, the zero stands for zero inches. Then, the three stands for three feet high, and the zero again is for zero inches. If a window is 28” by 54,” the four-digit number would be 2446 (meaning 2’4” x 4’6”).

What Are the Standard Double Hung Window Sizes?

Standard double-hung window sizes offer quite a few options. The widths range from 24 to 48 inches, and the heights come in sizes between 36 and 72 inches. You’ll find standard windows that match these different heights and widths in various combinations.

The standard widths available for double-hung windows are:

  • 24 inches
  • 28 inches
  • 32 inches
  • 40 inches
  • 44 inches
  • 48 inches

Standard heights for double-hung windows are:

  • 36 inches
  • 44 inches
  • 48 inches
  • 52 inches
  • 54 inches
  • 60 inches
  • 62 inches
  • 72 inches

Keep in mind that the actual size of the window is ½ inch smaller all around. This decrease in size accounts for flashing and insulation that gets added around the window during installation.

Therefore, a 44” by 44” window is actually 43 ½” x 43 ½”. A 24” x 36” window would be 23 ½” x 35 ½”, and so on.

Do Window Sizes Include the Frame?

Typically, vinyl and aluminum windows’ call sizes include the frame, sash, and glass. Wood windows usually don’t include the frame in their call sizes, and instead, they refer to only the glass. So a wood window that’s 36 inches wide would actually be closer to 37 ½” when you add in the frame.

In most cases, a wood window with the same call size as a vinyl window would have more visible glass. But, since manufacturers can vary on how they label their windows, it’s always wise to ask for details.

Can You Install Two Double Hung Windows Together?

You can achieve a whole new look and elevate your home’s curb appeal with twin double-hung windows. Twin double-hung windows are essentially two double-hung windows installed side by side.

If you plan to install separate windows next to each other, typically, you need to join or mull them together. After putting two windows together, you create a mullioned window.

Video: How to Mull Two Vinyl Windows Together

What Size Is A Twin Double Hung Window?

Installing two separate windows side by side essentially doubles the width of your individual window. But, you can also purchase ready-to-go twin double-hung windows that are encompassed within one single frame.

Many times, manufacturers might have these styles of windows available in custom sizes. You can find tons of different sizes depending on where you shop. For example, this size chart from America Craftsman features countless sizes of twin double-hung windows.

The smallest starts at 18” by 30”, and the largest is 48” x 62”. Other companies will likely offer similar sizes. Therefore, it’s always wise to shop around and ask for details.

How Do You Measure for Windows?

Measuring properly for windows is critical to getting precisely what you need. If you’re not confident with your number, it would be a good idea to have a professional do the measuring. For new construction, your contractor or window installer should take care of it.

If you’re purchasing replacement windows, the company or your installer should come out and measure. This service is typically included in the cost of the windows and installation.

But, if you’re confident in your DIY measuring skills, keep these tips in mind.

Measuring for Replacement Double-Hung Windows

When getting replacement windows, you can often simply measure your existing window. But, make sure you get an accurate reading. If you go too small, you might be able to make up a minuscule difference with trim and caulk.

However, if you go too big, you’ll need to return the windows or cut your wall. Once you cut into the wall to make a larger opening, you’ll need a permit for installing windows.

  • To measure the width, measure across the window between the inside of the jambs. Measure the top, middle, and bottom, and use the smallest as your width.
  • For the height, measure from the top of the sill to the top of the opening. Take a measurement at the right, middle, and left, and use the smallest number.

Measuring for New Construction Double-Hung Windows

You’ll do a similar process for measuring for new construction windows, but you’ll measure between the studs.

  • Get multiple horizontal measurements at the middle, top, and bottom of the opening. 
  • Then, take multiple vertical measurements at the left, right, and middle. Use the smallest numbers to determine your window size.

Video: Measuring for New Construction Windows

What If A Standard Double Hung Window Size Won’t Fit?

Sometimes, standard double-hung window sizes won’t work for your design. Perhaps you want to add a smaller window in a bathroom. Or you want an extra-large twin or triple double-hung window in your great room. No matter the reason, if standard sizes won’t work, you need to order custom windows.

Custom-Size Double-Hung Windows

You can get custom-size double-hung windows in pretty much any size you need; they’re custom. But, get quotes from several companies since going custom comes with a large price tag.

It’s certainly easier to install custom-size windows in new construction. You can make the opening any size you need while building. Trying to go bigger or smaller in an existing opening requires a bit more work.

Can I Install a Smaller Double Hung Window in a Larger Opening?

Changing the window opening size is possible, but it’s best left to a professional. Once you start changing walls, you’ll likely need a permit anyway. Plus, if putting in a smaller window, you need to make sure you properly close in the extra space.

It’s important to consider your home’s structural integrity, efficiency, and overall look. Putting a smaller window in a larger opening doesn’t always mean you need a custom window.

In fact, you might be opting for a smaller window to get a standard size. However, you will still need a contractor or professional installer to handle closing in the area properly.

Wrapping Up Double Hung Window Sizes

Opting for standard-size double-hung windows can save you time and money. You can find standard sizes ranging from 24 to 48 inches wide and 36 to 72 inches tall.

Always double check with the manufacturer that you’re getting the right size before you order your windows. If a standard size doesn’t work, you can opt for custom-sized windows instead.

Stacy Randall
Stacy Randall

Stacy Randall is a wife, mother, and freelance writer from NOLA that has always had a love for DIY projects, home organization, and making spaces beautiful. Together with her husband, she has been spending the last several years lovingly renovating her grandparent's former home, making it their own and learning a lot about life along the way.

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