What Are Standard Window Sizes?

When looking for new or replacement windows for your home one of the first things that you may think of is the windows size.

Windows, especially custom-made ones, can tally up the costs in any home renovation project. Lucky for homeowners, manufacturers have standard sizes to lessen the burden of crafting, manufacturing and installing windows.

But what are standard window sizes and what do you need to know before replacing or installing windows?

standard window sizes

Your Window Sizing Basics

Imagine a home with windows. Now, imagine your neighbor’s home and their windows.  How about picturing your family and friends’ homes and the windows that let light into their spaces? That’s a lot of different windows: shapes, styles, types—and sizes.

Manufacturers simplified the entire replacement window sizing process to help homeowners like you find the standard window sizes needed for a home. The window size notation is the combined width and height. A “2426” replacement window has a width of 2-feet 4-inches and a height of 2-feet 6-inches.

A side note to these measurements is that a manufacturer adds a half-inch to these measurements, giving them plenty of room for installation. If your window notation indicates a 44-inch x 44-inch opening, it probably measures 43 ½-inches x 44 ½-inches in actuality.

The half-inch adjusts for room on either side of the window for flashing materials and for it to operate properly.

When measuring window to determine the standard size, you’ll need to find out what the rough opening is. The rough opening, by definition, is the measurement from the inside of one side of the window frame to the other.

This is how manufacturers find the standard size of your window, and they’ll deduct that half-inch for the flashing to be installed and the window to be made plumb.

Standard Window Sizes: Helpful Guide

Double Hung Windows

double hung window size

Double-hung windows are the most common window types in homes across the country. Since these windows are so popular, double-hung windows come in many different standard sizes.

Their widths can range from 24-48 inches, while their heights range from 36-72 inches.

Picture Windows

picture window size

Big, broad, and beautiful, picture windows are ideal for rooms with a scenic view and lots of wall space that can improve your home’s curb appeal.  They have a level of architectural appeal that other window types cannot match.  Most picture windows don’t open, but they do come in multiple standard sizes to fit in any home.

Widths range from 2-feet to 8-feet and heights range from 1-foot to 8-feet tall.

Common, standard widths for picture windows are:

  • 2-feet
  • 3-feet
  • 4-feet
  • 5-feet
  • 6-feet
  • 8-feet

Popular and standard heights for picture windows include:

  • 2-feet
  • 3-feet
  • 4-feet
  • 5-feet
  • 6-feet
  • 7-feet
  • 8-feet
  • 18-inches
  • 52-inches
  • 62-inches

Bay Windows

bay window size

Similar in a sense to a picture window, a bay window can really open up your home. Bay windows offer more unique architectural traits than a standard, double-hung window, filtering in much more light like that of a vast picture window. They’re more appealing, due to their ornate features that traditionally come with their design and because they are quite large.

A bay window’s standard width ranges from 3-feet, six-inches to 10-feet, six-inches. Its standard size height ranges from 3-feet to 6-feet, six-inches.

Sliding Windows

sliding window size

As their name suggests, these windows open back and forth on a track, making for an excellent style in a small space that requires easy ventilation, like above a kitchen sink or in a small bathroom. These windows are notably wider than they are taller.

Sliding windows’ standard sizes have widths that range from 36-inches to 84-inches and heights that start at 24-inches to 60-inches tall.

Common and standard sliding window widths are:

  • 36-inches
  • 48-inches
  • 60-inches
  • 72-inches
  • 84-inches

Standard heights for sliding windows are:

  • 24-inches
  • 36-inches
  • 48-inches
  • 60-inches

Awning Windows

awning window size

Offering plenty of ventilation like its cousin style (casement window), the awning window is hinged at the top and opens outward.  Open your awning window during a light rain and the weather won’t bother you as these windows are considered virtually weatherproof.

Standard sizes for an awning window include widths that begin at 2-inches to 3-feet, 10 1/8-inches and heights that start at 1-foot, 8-inches to 7-feet, 8 7/8-inches high.

Casement Windows

casement window size

These windows are styled to open from the side and are ideal for areas of the home that require a little extra help ventilating, like a kitchen or a bathroom.

Standard sizes include widths that range from 1-foot, two-inches to 2-feet, 11.5-inches, and standard heights beginning at 2-feet, 5.5-inches to 6-feet, 5.5-inches.

Standard Window Sizes: Measuring Stays the Same

There are a lot of window styles and sizes out there, but measuring them to find their correct, standard size is a consistent process across the board.

Knowing what standard size windows your home has will make it all the easier to find and purchase replacement windows from a manufacturer when the time comes.

Leave the Window Measurements to the Professionals

professional window measure technician

The process is simple and straightforward. We all like to get down and do the work ourselves. However, window measurements and finding out the window sizes that will fit right into your home is not an easy task.

You don’t want to leave out any measurement out because then the installation or replacement will go entirely wrong. At Feldco, our professional measurement technicians and staff are trained to precisely measure windows so you can benefit from high energy efficiency. Don’t underestimate standard window sizes and measurements, let Feldco handle that for you. Speak to a product specialist and get a free quote online today.

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