What Are Casement Windows? A Detailed Expert View

Casement windows are one of the most popular types of window for homes in the UK. Easy to open, available in several materials and with plenty of glazing options, casement windows are affordable and complement traditional and contemporary homes effortlessly.

At Green Doors, we sell a dynamic range of new and pre-loved casement windows, and our experts have written the following guide that covers:

• What are casement windows
• What are their benefits
• What different types exist

Read on to learn all about this important homeowner topic.

What Are Casement Windows?

The term “casement” is defined as the part of the window that opens. Casement windows date back to the 18th century and are traditionally hinged at the side. This is instead of sliding open or tilting. Think of casement windows opening like a door, with the hinges being added to either the side of the frame or the top or bottom.

How Do Casement Windows Work?

Hinges and Opening Mechanisms

Casement windows are attached to the frame by side-mounted hinges and open outward like a door. Most modern designs use a hand crank that turns a gear-driven arm, allowing smooth, controlled opening and closing.

Some traditional styles may use a push-out mechanism with a handle and stay arm to hold the window in place. When closed, a tight seal is created as the sash presses firmly against the frame, improving energy efficiency.

Single vs Double Casements

A single casement window features one sash that opens from either the left or the right. Double casement windows, also called French casements, have two sashes that open from the centre without a vertical post, offering a wider, unobstructed view.

Ventilation and Usability Benefits

Because they open fully outward, casement windows allow maximum airflow. The angled sash can also catch side breezes and direct fresh air indoors, making them ideal for ventilation and easy operation.

4 Types of Casement Windows

1. Side-hung Casement Windows

This is the most traditional type of casement window, where it is hinged at the side and the window will swing open, up to 90°, like a door.

2. Top-hung Casement Windows

Also labelled awning windows, top-hung casement windows are hinged at the top and open from the bottom. It’s a great choice for stopping the rain from coming in during bad British weather.

3. Flush Casement Windows

A flush casement window fits tightly into the frame when closed. It’s become the popular choice for many over the years, as it provides a modern aesthetic and is typically made using aluminium.

4. Steel Casement Windows

Steel casement windows offer exceptional durability and strength that allow for very thin frames and sightlines. They also come with thermal breaks to enhance thermal efficiency, and many choose these as they provide an industrial aesthetic that suits both traditional and contemporary properties.

Benefits of Casement Windows

• Easy operation – Simple opening and closing make casement windows ideal for any area of the home.
• Great ventilation – Casement windows provide maximum airflow and help cool homes in the warmer months.
• Very secure – Locks are embedded within the frame, and the windows are tightly sealed when shut, making it very difficult to force entry.
• Versatile material options – uPVC, wood, aluminium and steel are all material options for casement windows, providing a wide range of choices.
• Low maintenance – Thanks to durable materials, casement windows are very low maintenance.
• Energy efficient – An airtight seal is created when closed to greatly reduce heat loss.

Casement Windows vs Sash Windows

Opening Style

Casement windows are hinged at the side and open outward like a door, usually operated by a crank or handle. In contrast, sash windows slide vertically or horizontally within the frame using a system of cords, weights or springs. Casements open fully for maximum airflow, while sash windows typically allow ventilation from the top, bottom or both.

Appearance

Casement windows are so popular because they offer a clean, modern look with large, unobstructed glass panes that work for most homes. Sash windows have a more traditional aesthetic, often featuring glazing bars that divide the glass into smaller sections.

Typical Property Styles

Casement windows are common in contemporary homes and modern renovations. Sash windows are strongly associated with Georgian, Victorian and Edwardian period properties, where maintaining architectural character is important.

Explore Our Range of Preloved Casement Windows

What are casement windows? They’re the ideal type of window that opens to the side and provides excellent ventilation and security, easy opening and closing, great energy efficiency and low maintenance. At Green Doors, we have an amazing range of preloved casement windows in a range of colours and materials, all ready to install and at low prices.

We also sell a range of other windows, front doors, back doors, patio sliding doors and distinct styles that have all been refurbished instead of wasted. For any help choosing casement windows or our other preloved products, get in touch with us today.

Frequently Asked Questions