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French Windows

Order made-to-measure uPVC French windows online from AWM Glass. Made to your supplied dimensions, they provide a practical way to introduce a wider opening, more ventilation and plenty of natural light.

A French casement window uses two opening sashes. The flying mullion moves with the secondary sash, so opening both sides creates a clear, uninterrupted opening without a fixed central bar. This makes the design suitable for wider openings and, subject to the finished dimensions and building requirements, some emergency escape applications.

Choose a standard French Window or a French Window with Toplight below, then configure the size, colours, glazing and accessories. All products are supplied only, with delivery available across England, Scotland and Wales.

French Windows

French Window

£237.60
£378.00

How French Casement Windows Work

A French casement window has two opening sashes positioned side by side. One sash is opened first, followed by the secondary sash when the full opening is required.

Unlike a conventional casement arrangement with a fixed central mullion, the French design uses a flying or floating mullion carried by the secondary sash. When both sashes are open, the mullion moves out of the opening with the sash.

This creates a wide, unobstructed opening that can improve ventilation and provide easier access through the aperture. When closed, the two sashes meet securely at the centre to form a weather-resistant window.

This arrangement is especially useful where a wide opening is preferred but the available space does not suit a single large sash.

Standard French Window or French Window with Toplight?

Standard Design

Choose the standard configuration when you want the two opening sashes to occupy the full window height. It provides a simple, balanced appearance and the largest possible opening within the selected frame size.

VIEW STANDARD FRENCH WINDOW

Design with Toplight

A toplight adds a separate glazed section above the two opening sashes. This can suit taller apertures, help match surrounding windows or provide additional glazing while keeping the main opening sashes at a practical height.

VIEW FRENCH WINDOW WITH TOPLIGHT

Made-to-Measure Options and Specifications

Each uPVC French window is manufactured to the width and height entered during configuration. Available choices depend on the selected product and dimensions, so review the options shown on the product page before ordering.

Profile systemAdvance 70 five-chamber uPVC profile
ConfigurationStandard design or design with a toplight
GlazingArgon-filled Low-E double glazing as standard, with additional glazing options where available
ColoursA selection of internal and external frame finishes
Handles and hardwareChoose from the options offered in the online configurator
Additional optionsCills, trickle vents, fixing kits, thermal spacer bars and decorative glazing options are available on selected configurations
ManufactureMade to the overall frame dimensions supplied with the order

Explore the available frame finishes in our colour guides, or browse compatible uPVC window accessories.

uPVC French window with flying mullion and wide opening

Energy Efficiency, Weather Performance and Security

The Advance 70 five-chamber uPVC system and Argon-filled Low-E double glazing help reduce heat transfer through the frame and glass. Correct measuring, installation and sealing are also important to the finished window's overall thermal and weather performance.

The window system has been tested for weather performance, operation and security. The exact specification depends on the size, glazing and options selected, so check the individual product configuration carefully if your project has particular performance requirements.

Measuring and Emergency Escape Requirements

These windows are manufactured from the dimensions supplied with your order, so accurate measuring is essential. Measure the structural opening in several places, allow the appropriate fitting tolerance and follow our window measuring guide before submitting your final sizes.

A French opening can provide a larger clear aperture than some standard casement arrangements. However, suitability for an emergency escape window depends on the finished clear opening, its position, the installation and the applicable building requirements. Confirm these requirements for your property before ordering rather than relying on the window style alone.

Supply-Only Windows and Nationwide Delivery

AWM Glass supplies made-to-measure windows for installation by you or your chosen tradesperson. Installation is not included, so arrange a competent installer if you are not experienced in fitting replacement windows.

Delivery is available across England, Scotland and Wales. Current production estimates and delivery information can change, so check our live guidance before planning removal or installation work.

Frequently Asked Questions

A flying mullion, sometimes called a floating mullion, is the vertical section carried by the secondary opening sash. It moves out of the way when both sashes are open, creating a wide aperture without a fixed central frame section.

A standard casement arrangement may include a fixed mullion between adjacent opening sashes. A French casement design allows the centre section to move with one sash, producing a clearer and generally wider opening when both sides are open.

Potentially, but the style alone does not make a window compliant. Suitability depends on the finished clear opening, its height and position, the room and the building requirements that apply to the project. Check the required dimensions before placing your order.

No. AWM Glass supplies made-to-measure products for installation by the customer or their chosen installer. If you are not confident measuring or fitting the window, use an experienced tradesperson and confirm all dimensions before ordering.

Explore More Made-to-Measure Windows

Compare other configurations, opening styles and frame materials in our wider window collection.