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If you’re new to Casement Windows then keep reading this guide as it will help you to see how they can fit your application. If you are familiar with this type of windows and want to discuss the options and features for your installation, then skip the guide and contact our dedicated teams in your area below:

A popular choice in medieval Europe, the casement windows have maintained their strong following around the world because of their attractive styling, easy operation and an ever-growing number of designs and materials.

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Built to fit most any architectural style, modern casement windows are typically installed vertically and use classic side-hinged models that swing open manually or with a crank. While 18th-century glass manufacturing was limited to producing only small pieces of window glass that had to be attached with lead strips, today’s casement styles exhibit unencumbered visibility and optimal airflow.

Casement windows can be used in new construction or as replacement products. To be sure you get the windows that are most suited to your application and needs, review this ultimate guide to casement windows.

Casement Windows Installation

new casement window
Combination of casement and fixed windows with wood trim. Calgary window replacement project

A common installation sets the window vertically so it opens like a door. This allows the window to open completely. Casement windows can be used individually or mulled together. When connected side-by-side, end windows are usually operable and the centre units remain fixed.

An awning window is a casement window turned on its side. The horizontal installation works well for kitchen areas, especially above the sink where it can be difficult to reach a traditional window. Opening and closing is easy with a simple crank of the handle. Awning windows can open to a maximum of 45 degrees allowing sufficient ventilation without straining to reach.

Installing an awning window higher on the wall in a bathroom or close to kids’ reading nook will provide natural lighting and additional ventilation without sacrificing privacy. The hand crank is located along the bottom of the window for easy access.

They also have gained popularity as accent windows above doors and fixed vertical casement windows. They work great for bringing more light and air into the room no matter what Mother Nature has in store. A horizontal casement window can be left open during rainstorms as the water will run off the glass pane instead of coming into the house.

Casement Windows Frame Materials and Finishes

vinyl casement windows

While oak frames were the norm for vintage-era designs, they were bulky and offered limited colour selections. By the end of the 19th century, manufacturers began offering different framing materials to improve aesthetics and provide a choice of finishes. While the new materials required painting, homeowners could select distinctive hues to match their architectural style.

Modern framing materials include:

  • Wood—although susceptible to decay, it is still a popular choice for its natural beauty. Wood frames are available unfinished, primed or pre-painted to match the exterior decor and colours. This material is very strong and durable. It has minimal condensation as wood has a low heat and cold transfer. Wood is also more expensive than other materials.
  • Clad/Combination—wood frames bonded with extruded aluminum, vinyl or fiberglass. This frame (with any type of cladding) reduces maintenance and increases durability. It’s very weather-resistant and can include energy-efficient glazing options. The exterior finish comes in a variety of colour coatings while the wood interior can be stained or painted. Unsealed edges may allow moisture under the cladding and contribute to rotting, mold or mildew.
  • Vinyl—offers a low-cost, high-performance alternative to wood. New manufacturing techniques have improved the look and quality of these window frames. Vinyl is very energy efficient and is often insulated with foam. It is both non-corroding and UV-resistant so its finish can be preserved. Many manufacturers are now adding to their colour line for both interior and exterior customizing. Woodgrain options are offered for a classic interior wood look without the maintenance.
  • Aluminum—the strongest and most durable of all window materials. Similar to vinyl, aluminum frames are a low-cost, low-maintenance option. It is usually insulated to stop moisture build-up and insulated to prevent heat loss.
  • Fiberglass—although up to 25-percent more than vinyl windows, fiberglass is gaining in popularity because of its real-wood look without the maintenance. Made from glass fibers and resin, it can be painted to match the exterior decor, is rot-resistant, is extremely strong, and is an excellent insulator.

Check Out: Advantages and Disadvantages of All Window Materials

Casement Windows Sizes and Shapes

two casement windows

Casement windows are often used in areas where the height is greater than the width. They come in various sizes and arrangements. They are either fixed (not operable) or hinged on the right or left to open out.

Single-unit (one-lite) standard widths range from 1′-5″ to 3′-0″ and are configured in 2-wide, 3-wide, 4-wide, and 5-wide styles mulled together for superior ventilation and unobstructed view. Standard and custom sizes can be combined with equal-sized sashes, larger fixed centre sash with operable flanking windows, stacked with transom window on top, or any number of other arrangements.

Awning windows are wider than they are tall and are often used to meet natural light and ventilation building codes.

Check Out: Casement Windows Styles

Efficient, Secure and Private

double glazed casement window

With energy costs on the rise and the majority of heat lost through your windows, it’s crucial to take advantage of new technologies that improve energy efficiency. Choose an Energy Star-rated window that has a low U-factor and save an average of 12-percent on your annual utility bills. Add some of these options and save even more:

  • Double- and Triple-Pane Windows—multi-pane windows are constructed with two or three sheets of glass with sealed air pockets between the layers. Spacers and Argon or Krypton gas are added to prevent air from flowing in or out.
  • Low-E Coatingslow-emissivity coatings reduce the amount of ultraviolet and infrared light that enters during the warmer summer months. Sunlight enters the home but does not overheat. In colder winter months, heat gain comes into play with a greenhouse effect. Any heat generated inside is not allowed to radiate back out.
  • Visible Transmittance Rating (VT)—be careful not to block too much light from entering your home. The darker the glass, the less light that enters, and the more energy is used on electric lighting.

For windows and doors ratings, ENERGY STAR has broken Canada up into three distinct climate zones. The majority of the Canadian population resides in climate zone 2. As such, to be considered efficient casement windows in Calgary, Edmonton, Winnipeg, most Saskatoon, Regina and Vancouver any window must have a minimum ER rating of 29.

Canadian Climate Zones by Energy STAR

home windows energy ratings

ER Ratings are a number given to windows, based on a calculation of different performance factors. These include things like the U-Factor and Solar Heat Gain Coefficient. The ER rating has been created specifically to make it easier for consumers to understand and compare window performance across different manufacturers.

U-Factor is a calculation of how conductive a window is, how it is affected by convection heat loss and the emissivity of the glass in the panes. At the very basic level, the lower the U-factor, the better your window is at keeping heat inside.

SHGC: The Solar Heat Gain Coefficient is a measure of how much heat from the sun a window gains. Although ideally you want as much heat from the sun in the winter months, most modern windows with high SHGC end up overheating the home. High SHGC factors are great for windows that see very little direct sunlight and can maximize energy gains in those places. The lower SHGC, the less heat from the sun your windows let through.

In addition to keeping heat from moving through them, energy-efficient windows are also effective at keeping noise levels down. While not entirely “sound-proof,” double- and triple-pane windows will save you money and help you enjoy some peace and quiet.

If safety is a concern from falls or break-ins, tempered glass is the perfect choice. It is stronger and more impact-resistant than standard window glass for better peace of mind. Casement window designs close tight to provide a weatherproof seal that’s inaccessible from outside for improved security.

In areas where you want t keep people from looking into your home, such as in bedrooms and bathrooms, you can choose opaque etched or frosted glass to allow light to enter without compromising privacy.

Screens are installed on the interior side of the frame. New materials provide improved visibility, better ventilation and insect protection than standard products.

Casement Windows Drawbacks

There are a few issues related specifically to casement and awning windows:

  • Standard air conditioning units will not fit. It will be necessary to purchase a special unit that costs twice as much as a double-hung model.
  • Hardware can be difficult to operate and susceptible to breakage.
  • Casement windows open out, so the sash edges are exposed to all weather conditions. They may lead to faster deterioration.
  • If left open during strong winds can over-extend or break the window.
  • It can be difficult to get larger windows with more glass area.

Casement Windows Maintenance

Casement windows require very little maintenance. When open, both front and back of the window are easily accessed from the inside for glass cleaning. It’s recommended to periodically check the screws, hardware and hinges for breaks or any malfunction.

Clean debris and dirt from window tracks with a small brush or vacuum. Use mild soap and water to wash tracks, sills, glass, and frames. Remove cranks, clean with a wire brush, and lubricate hardware with dry silicone spray. Polish exposed hardware to maintain the finish.


Casement windows are an excellent choice for historic and modern architectural styles. The wide variety of frame materials, energy-efficient options and easy maintenance make this window design one of the best values for both new installations and replacement products.

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