The Comprehensive Guide to Casement Window Anatomy

Casement windows have been a popular choice for homeowners for centuries, offering a unique blend of style, function, and versatility. In this comprehensive guide, we will delve into the anatomy of casement windows, exploring their various components and how they work together to create a window that is both aesthetically pleasing and functional. With over 1000 words, this article aims to provide you with a thorough understanding of casement windows and their various features.

What is a Casement Window?

Before diving into the anatomy of a casement window, it's essential to understand what a casement window is. Casement windows are hinged windows that open outward, usually operated by a crank or handle. They provide excellent ventilation, unobstructed views, and a classic look that complements various architectural styles.

Now that we have a basic understanding of casement windows, let's explore their anatomy in more detail.


The frame is the outermost component of a casement window, providing structural support and housing the other window components. It typically consists of four parts: the head, the sill, and the two jambs. The head is the horizontal top piece, while the sill is the horizontal bottom piece. The jambs are the vertical side pieces that connect the head and sill.

Frames can be constructed from various materials, including wood, vinyl, aluminum, and fiberglass. Each material offers its own set of advantages and disadvantages in terms of durability, maintenance, and energy efficiency.


The sash is the part of the window that holds the glass panes in place. It consists of horizontal and vertical bars, called rails and stiles, respectively. The sash is connected to the frame by hinges, allowing it to swing open and closed.

Casement window sashes can be made from the same materials as the frame, with wood and vinyl being the most common choices. The sash design can vary, from a simple, unadorned style to one featuring decorative elements like grids or muntins.


The glass panes in a casement window serve several purposes, including providing natural light, insulation, and protection from the elements. Modern casement windows often feature double or triple glazing, which consists of two or three panes of glass separated by a spacer and filled with insulating gas. This design helps improve energy efficiency and reduce noise transmission.

In addition to the number of panes, homeowners can also choose from various glass options, such as low-emissivity (Low-E) glass, which helps reduce heat transfer, or impact-resistant glass, which offers increased protection against storms and break-ins.


Hinges are the hardware components that connect the sash to the frame, allowing the window to open and close. Casement windows typically feature two types of hinges: butt hinges and friction hinges. Butt hinges are the traditional choice, consisting of two plates connected by a pin. Friction hinges, on the other hand, use a sliding mechanism to control the window's movement, offering a smoother operation and improved weather resistance.


The operator is the mechanism used to open and close a casement window. Most casement windows use a crank or handle operator, which is mounted on the jamb and connected to the sash by an arm. Turning the handle rotates the arm, pushing the sash outward or pulling it inward. Some casement windows, particularly those in hard-to-reach locations, may feature a push-out operator, which requires the user to push the sash open manually.


Weatherstripping is the material used to seal the gaps between the sash and frame when the window is closed, preventing drafts and improving energy efficiency. There are several types of weatherstripping available, such as adhesive-backed foam tape, V-strip, and door sweeps. The best type of weatherstripping for your casement window will depend on factors like the window's age and the local climate.

Locking Mechanism

Casement windows typically feature a locking mechanism to secure the window when closed, improving both safety and energy efficiency. The most common type of lock is the multi-point lock, which engages at multiple points along the jamb, providing increased security and a tighter seal. Other options include single-point locks and sliding locks, which may be more suitable for certain window sizes or styles.

With this comprehensive guide to the anatomy of casement windows, you should now have a solid understanding of the various components and features that make up these popular window styles. Whether you are considering new windows for your home or simply looking to better maintain your existing casement windows, this knowledge will prove invaluable in making informed decisions and getting the most out of your windows.

Casement Window


Casement windows are the most common style of window. They feature hinged panels that swing open and closed. Casement windows are available in single panels or multiple panels. The direction a door swings, either to the right or the left, is called the handing. In addition to handing, window are identified as either inswing or outswing depending on whether they open into the house or towards the outside.


Our team of experts will work with you to develop a bespoke plan that fits your needs. We take a holistic approach to the planning process, combining our technical expertise with our knowledge of customer requirements and project constraints.


Freedom to dream "truly custom-made"

Doorwin provides one-stop solution for professional windows doors manufacturer and installation. We have been serving customers with our high quality and branded products in United States, Asia and worldwide.


This newly built private house is in Sydney, Australia. The area occupied by the fenestration system in our scheduled design drawings was up to more than 110 square meters. A wide range of design details made the perfect mix of modern aesthetics and traditional sophistication, the simulated vertical hung windows with tilt & turn opening systems in this home are absolutely breathtaking. SDLS (Simulated Divided Lites with Spacer Bar) brings some historical vintage feeling to the whole building without losing any energy saving performance. Long narrow fixed windows creating larger-than-life expenses, coupled with German high-end systems made this project stand out from the rest.

Simulated Hung Window with Tilt & Turn Openings

The client's idea was to maintain a certain vintage feel, and our aim was to meet the energy efficiency needs and standards of modern houses as much as possible while maintaining a retro design. Doorwin’s 61S simulated hung windows with tilt & turn openings is a respectful modernization of a classic architectural masterwork.

Why choose the tilt and turn opening method?

Because it generally has better air seals than sliding, single hung, or double hung window frames. Tilt and turn windows form a complete seal when fully closed, this means they are less prone to water leakage, and cold draughts and you’ll keep more of your heating indoors where it belongs. They can be opened in the upper tilt way to ventilate at a minimum opening status and are easy to clean outside of the glass; when there’s a good day, they can be opened as normal inward casement windows.

Large Energy Efficient Fixed Windows

Our well-crafted bespoke systems enhance the functionality and panoramic view of this modern house.

Huge, fixed glass walls up to seven meters long and two meters high bring great lighting and open views, making it really refreshing to the mind. Five meters high long narrow windows give the whole building a contemporary aesthetic.

Every window’s placement and shape not only add to the uniqueness of this home but also provide a more energy-saving ability for the owners.

Doorwin energy-efficient integrated glazing units feature double-pane glass, warm-edge spacers, argon gas fill, Low-E coatings, and fully tempered glass, they can not only create a comfortable and natural indoor environment but also save electricity bills and heating bills of more than 100 USD for the owner, it’s a real bargain compared to choosing a regular glazing set.

Custom Designed Thermal Break Aluminum Entry Door

Aluminum Door offered an air of uniqueness and elegance to a home. With their luxurious patterns and beautiful finishes, it provides this house with a bounty of aesthetics and security. Aluminum entry doors allow you to resist any weather extremes, corrosion, and pests. So aluminum is one of the most resilient and durable materials you can select for front doors considering the price/performance ratio.

With pieces of double panes, and Low-E tempered glass. The door provides a good insulation performance.

Custom Designed Grilles and Transom

Divided lite windows and doors offer unique architectural solutions for buildings without compromising energy efficiency or aesthetics. Doorwin provides multiple muntin and glass options to customize your divided lite windows and doors. Further customization is available with a variety of colors and materials, creating an infinite number of design combinations to best suit your style.

In this project, we use SDLS (simulated divided lites with spacer bars), these bars permanently adhere to both sides of the glass, and spacer bars are installed between the glass, this is the most energy-efficient way to create the look of classical décor grilles. The windows in the bathroom bedroom and study have an Arch Transom Design, making these rooms, which are often used by the owner, have some traditional aesthetics.

BTW, Doorwin offers free design assistance, so if you need a custom design like this one, contact us right away and we will provide you with the most aesthetically and functionally pleasing design solution.

German Imported Hardware System

For windows and doors, hardware is as important as the engine is to the car. The continuous technological innovation of the European hardware industry has strongly promoted the performance improvement and functional innovation of windows and doors. In this project, Doorwin uses Hoppe™ multi-point locks, hinges, and handles from Germany.

Multi-point lock systems provide not only the burglar-resistance but also a tighter compression seam, making the window keeps good energy-efficient performance. Together with Technoform Bautec’s insulation edge bond and sealant strips, these make up our products' top insulation and energy-saving performance.

Save Your Money On Installation Costs

We have several international patents to reduce clients’ labor costs, such as our unique flanges and assembly type tubular design, which is different from the other products on the market. What sets us apart among Chinese counterpart is that all our products are equipped with nail fin structures for quick and easy installation. Labor costs during installation may exceed of the window and door price, therefore, our exclusive patent allows users to not only get a significant increase in installation efficiency, but also greatly reduce the labor cost of window and door installation. A cost that may bring you unexpected savings that far exceed the price difference you may care about now.

Free Design Assistance

With our own expertise, we provided the no-cost design development and contract documentation with CAD & BIM drawings, including elevation, details about the project, and installation help.

Before production, we will provide accurate sample drawings, which will clearly show the cross-sectional pattern, size, opening method and direction, pattern of the warm spacer, and the installation nodes. We will not go into production until you have signed off on the drawing to ensure that you receive a final product that meets the exact requirements of your project.

About Doorwin

Doorwin's professional packing system guarantees all products are delivered safely and without any damage. We apply a four-point packing system. Firstly, adhesive plastic film is applied on interior wood frames and exterior aluminum frames to avoid scratches on the surface. Then, a paper board is applied after we apply air bubble film surrounding the whole windows/ doors to avoid any destruction or clash. Lastly, we place them into a durable non-fumigation plywood crate to avoid any possible damage during transportation.

With years of experience shipping our products worldwide, we could guarantee to ship our products to their final destinations intact and without any damage.

About Doorwin Factories

Doorwin is one of the most professional window & door manufacturers are known for its great customized products. In Doorwin, a variety of colors, styles, and sizes of products are available to meet the client’s unique requirements. We own three ISO9000-certified modern factories in China. With a factory area of 20,000 m2 and a production capacity of 100,000 m2 per year. Doorwin Group has the scale to ensure timely delivery and the flexibility to reduce manufacturing lead times to as short as 18 days.