Casement Window Size Guide

Updated:  January 23, 2020

Casement windows, which open from one side on hinges using a crank, provide a wide range of benefits to homeowners. Not only are they energy-efficient, easy to use and easy to maintain; they can also improve ventilation in your home and even strengthen your home’s security.

You will often see casement windows above sinks, countertops or appliances; however, they are ideal for just about any room.

If you’ve decided to invest in casement windows, this guide will help you in selecting the right size, configuration and style for your home.

Standard Sizes Of Casement Windows

Picking the “right size” of window is one of the most important choices to make when it comes to replacing or installing windows.

Windows installed in homes do not follow standard sizes but rather fall within a range that can be customized accordingly.

In Canada, both double- and triple-glazed casement windows have a size minimum of 14.25 inches in width by 18 inches in height. (This minimum exists because there comes a point where window manufacturers cannot make windows any smaller.)

In terms of the maximum range for casement windows, you can get double-glazed windows as large as 38 inches wide by 78 inches high. The maximum for triple-glazed casement windows is almost the same, at 37 x 78 inches.

Why the need for a size maximum? It’s due to the heaviness of the window. Going beyond the maximum could lead to hardware malfunction.

Casement Window Size Guide-Casement Window Standard Sizes-Weaver Exterior

Casement Window Configurations

What kind of window configuration do you envision for your space: one single casement window, or multiple casement windows?

Note that some casement windows can be “fixed,” meaning that they are simply a window that does not open (it does not have a crank). Many homes feature configurations using both fixed and crank casement windows.

When you consider multiple casement windows, you can choose for them all to be of equal size, or different sizes. As an example, if your configuration is three casement windows in a horizontal row, you can make the middle window the largest, with the neighboring “twin” windows smaller and of equal measurement to one other.

Not all configurations have to be side-by-side. You may wish to “stack” one window, such as a fixed casement window, above a casement window that opens.

Casement Window Size Guide-Casement Window Configuration-Weaver Exterior

Other Factors To Consider

There are three other main considerations that will affect which casement windows you choose to install: casing, brickmould, and jambs/jamb extensions.

Vinyl casing is the decorative trim that goes around your window frames on the outside of your home. Casings come in a range of sizes and styles and can help further seal the window frame, blocking cold air from coming inside.

Brickmould, like casing, is a material lining on the outside of the window. It fills the gap between the window frame and exterior part of your home’s siding. Visible to the eye, brickmould helps optimize your windows for energy efficiency.

Jambs are an interior vertical component that link the casing to the window frame, enabling your window to fit the opening and sit flush with the interior wall. If the depth of your frame is not as deep as the wall opening, jamb extensions can help make it fit. This kind of variability is why window installers must customize windows rather than work with standard sizes across the board.

Casement Window Size Guide-Image Of Casement Window-Weaver Exterior

Measuring For Casement Windows

f you want your casement window to perform to its maximum potential, it is imperative to get an accurate measurement of each window opening. Even a tiny error in measurement can negatively affect your home’s energy efficiency and even cause structural damage.

You can start by taking a general measurement of the width, height and depth of the open space that would be left if the window was to be removed. (For more tips on measuring for windows, read this blog.)

Then, call a professional window installer: an expert who will take care to measure within fractions of an inch and ensure you select and install the right casement window size into your home.

Get It Right The First Time

Now that you are informed about casement window sizes, it’s time to set up a free quote with Weaver Exterior Remodeling.

For more than 30 years, our experts have provided professional guidance to clients on the perfect type of casement window for their homes, and ensured their windows are properly measured and installed the first time. Because of our commitment to quality products and services, we are proud to have been named one of the three top window installers in Barrie.

Let’s start the conversation about how we can help you.

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Weaver has over two decades of experience and provides comprehensive installation services for windows, doors, and aluminum in the Barrie region, making it a convenient option for all project sizes.