Look for Hinges
An opening casement is connected to the frame by hinges rather than moving up and down on a sliding mechanism.
Window Style Guide
What Does Casement Mean on a Window?
A casement is an opening section of a window that is attached to its frame by hinges.
Most modern casement windows in UK homes are side-hung and open outwards, although top-hung casement openers are also common.
Quick Answer
What Is a Casement Window?
A casement window has one or more opening sections that are hinged to the window frame.
The most familiar type is a side-hung casement that swings outwards when you turn the handle. Casement windows can also be arranged with several fixed and opening sections within the same frame.
Identifying the Style
How Do I Identify a Casement Window?
Look for an Opening Sash
The glazed opening section, known as the sash or casement, moves away from the frame when the window is opened.
Look for a Handle
Modern casement windows commonly use a handle to operate and secure the opening sash when the window is closed.
Window Terminology
Which Part of the Window Is the Casement?
Technically, the casement is the hinged opening part of the window that holds the glazing.
The surrounding structure is the window frame. A larger casement window may contain several sections, with some opening and others remaining fixed.
Vertical sections dividing different areas of the window are commonly called mullions, while horizontal divisions are known as transoms.
Common Configurations
What Types of Casement Windows Are There?
Side-Hung Casement
The opening sash is hinged vertically at one side and normally swings outwards. This is one of the most familiar casement styles used in UK homes.
Top-Hung Casement
The hinges are positioned along the top of the opening section, allowing the bottom of the sash to move outwards.
Double Casement
Two opening casements can be positioned alongside each other, creating a wider opening when both sections are opened.
Spot the Difference
How Is a Casement Window Different?
Casement Window
Uses hinges to allow an opening sash to swing away from the frame.
Sash Window
Uses sliding sashes that move within the frame rather than swinging open on conventional side hinges.
Fixed Window
Does not open at all and is primarily used to provide glazing, natural light and views.
Practical Design
Why Are Casement Windows So Common?
Good Ventilation
Opening casements can provide a substantial clear opening, making them useful where ventilation is required.
Flexible Configurations
Opening and fixed sections can be combined in many different layouts to suit the size and shape of a window opening.
Wide Choice of Materials
Modern casement windows are available in materials including uPVC, aluminium and timber.
Common Misunderstanding
Does Every Casement Window Look the Same?
No. The word casement describes the hinged opening principle rather than one exact appearance.
Casement windows can have different frame materials, glazing layouts, colours and opening configurations. There are also standard and flush casement designs, which differ in how the opening sash sits against the outer frame when closed.
If you are choosing new windows rather than simply identifying the style, visit our casement windows page for the available design options.
Common Questions
Casement Window FAQs
What does casement mean on a window?
It refers to an opening window section that is attached to the frame by hinges.
How can I tell if I have casement windows?
Look for an opening sash attached to the frame by hinges. Side-hung casements are especially common and usually swing outwards when opened.
Do casement windows always open sideways?
No. Side-hung casements are very common, but casement window configurations can also include top-hung opening sections.
What is the difference between a casement and a sash window?
A casement opens using hinges, while a traditional sash window opens by sliding one or more sashes within the frame.
Are casement windows available in uPVC?
Yes. Modern casement windows are commonly available in uPVC as well as aluminium and timber.
Looking for New Casement Windows?
Explore our range of casement windows for traditional and modern homes across St Helens and the surrounding area.