Ultimate Guide to Casement Windows
The distinctive hinged design and unique silhouette of casement windows make them a popular element in historic as well as new-build homes. Here's what you need to know about buying, installing, and maintaining casement windows.
Casement windows—which first appeared in medieval times—have remained popular for centuries because of their good looks, simple operating systems, and evolving designs that stay in step with homeowners' form and function needs. Early 20th-century designs added charming silhouettes to homes built in the cottage, Tudor, and Gothic styles. Decades later, more streamlined versions popped up in factories—similar casement window designs now contribute progressive profiles to urban lofts and contemporary homes.
Adapting to most every architectural style, casement windows make a striking statement from inside and outside. Hinged much like a door, casement windows swing fully open (usually via a crank, though some can simply be pushed open) to maximize views and optimize airflow. The vertical designs are available in an array of styles, frame materials, and rectangular and square shapes. They are easy to clean—when open, both sides can be cleaned from inside.
Turn a casement window design on its side, and you get a horizontal awning-type casement window that swings out and up. This type of casement window hinges at the top, comes in a few shapes and sizes, and is well suited to use high on walls. Awning windows are good choices for use as basement casement windows. When open, the window acts as an umbrella, keeping falling rain and leaves from coming inside.
Both awning-style and other casement window designs tightly close, providing a weatherproof seal against drafts and moisture. Their unique locking systems, which aren't easily accessible from outdoors, strengthen a home's security.
There are a few drawbacks that come along with casement and awning windows. Because of their opening-outward design, casement window screens must be placed inside window frames, standard air-conditioners are not an option, and available window sizes are limited due to the weight of glass.
Types of Casement Windows
Casement windows fall into three categories, with each type available in a range of materials.
Single-frame casement windows are the most common casement window style. This type is one window frame that holds a single pane or multiple panes of glass separated by wooden strips. Double casement windows, which are also called French windows because there is no vertical center post, operate as a pair of casement windows that open outward and meet in the center when closed. Push-out casement windows are available as single-frame and double-frame styles; they simply are pushed out and held open via special operating systems.
New and replacement casement window frames are crafted of vinyl, aluminum, wood, steel, and clad wood. The most common exterior colors are tan, black, brown, bronze, white, and cream, but you can find them in other shades, such as green, yellow, and red.
Wooden casement window frames usually come unfinished so they can be painted or stained to suit your home's style and your design preferences. Some are available in primed versions or prepainted types. Wood frames minimize condensation and won't become as cold as other types of window frames.
Aluminum casement windows are light, easy to install, durable, and insulated to prevent heat loss and protect against moisture buildup.
Vinyl casement windows are inexpensive, heat- and moisture-resistant, and more likely to leak air over time.
Clad-wood casement windows have an exterior that is protected by aluminum, while the interior is stained or painted wood.
Steel casement windows boast old-world charm and heftier price tags than standard types of casement windows.
Casement Window Glazing and Glass Styles
Energy Saver, the Department of Energy's consumer resource guide, recommends considering how a window's glazing or glass can make your home more energy-efficient. Here are a few energy-saving window glass options to keep in mind while shopping for new or replacement casement windows.
Gas fills improve the thermal performance of windows with insulated glazing; inert gas, which has a higher resistance to heat flow than air, fills the space between the panes with inert gas. Heat-absorbing tints change the color of the glass so the glass absorbs a large portion of incoming solar radiation, which in turn reduces solar heat gain and glare. Windows with insulated window glazing are equipped with two or more panes that are spaced to allow for an insulating air space and then hermetically sealed. This type of glazing lowers a window's U factor (the rate of conducting nonsolar heat flow). Low-emissivity (low-E) coatings control heat transfer through windows with insulated glazing. Windows manufactured with low-E coatings typically cost about 10-15% more than regular windows, but they reduce energy loss by as much as 30-50%.
Remember to check that the casement windows you buy are Energy Star Certified for your region to ensure your home operates as efficiently as possible.
Casement Window Installation Tips
Cutting openings to fit new casement windows and installing those new windows are perhaps tasks best left to professional window contractors. Contact multiple contractors, shop various home centers, and get at least three bids before choosing a contractor—always check the references they provide to ensure your windows will be installed correctly, on time, and on budget.
Replacing existing casements with like-size windows is a task that a handy do-it-yourselfer can tackle with the help of a friend who is willing to hold up the weight of each window as it's fitted into an existing opening and then secured in place.
Always read and follow the window manufacturer's installation instructions. Keep old windows in place until you have inspected new ones for damage and verified their size. Rent scaffolding to safely install windows on upper levels. Always wear eye and hand protection when handling glass and fiberglass insulation.
What You Need
- 4-foot level
- Circular saw
- Drill and drill bits
- Utility knife
- Caulk and caulking gun
- Wood shims
- Drip edge
- Casing nails
- Fiberglass insulation
How to Install Casement Windows
Home Depot supplies this general overview of steps you'll need to take to install a replacement casement window. Read them over carefully to determine whether your skills are up to the task.
- Remove the existing window and test-fit the new one.
- Trace around the molding.
- Cut the siding along the outline.
- Cut the drip edge.
- Caulk around the molding.
- Set the window into the opening.
- Level the window.
- Tack the window in place.
- Use shims to fill the opening between the jambs and framing.
- Ensure the window fits correctly.
- Predrill holes in brick mold, if applicable.
- Apply molding over the window's nailing fin.
- Fill with insulation.
- Trim the shims.
- Apply caulk to seal the perimeter.
If the process appears problematic, remember that, along with professional window contractors, most home centers will install replacement casement windows.
Maintaining Casement Windows
One of casement windows' greatest benefits is that both sides can be cleaned from the inside of your home. Casement windows should be cleaned once or twice a year, and periodic checks should be done to determine that hinges, screws, and hardware are securely in place.
To clean casement windows, simply unlock each casement, open the windows wide, and use a small brush to clean debris and dust from the windows' tracks. Use your vacuum's crevice tool to remove hard-to-reach dirt in the tracks. Wash window tracks, sills, and interior and exterior glass and frames with a mixture of mild soap and water; squeegee off excess soap and water, and dry with a clean cloth as needed. Remove window cranks, and clean the cranks' working parts with a small wire brush; lubricate the gears, window tracks, and hinged hardware with a dry silicone spray. Take time to clean and polish window cranks and other exposed hardware to preserve their finishes and renew their shine.