Sieger Slim Casement

An Award Winning Window System


The Sieger® Slim Casement Window is an award-winning aluminium window system. The modern aluminium profiles can be designed into a variety of configurations to suit the requirements of the project. These slim windows are a fantastic choice for both new buildings and replacement windows. They provide a simple yet effective window design that boasts high levels of thermal performance.

Sightline: 65mm across vent and frame

Thermal Insulation: Uw values from 1.1 W/m2K

Security: PAS 24 Certified

Max Window Size: side hung windows 700mm wide / 1300mm tall, top hung windows 1200mm wide / 1300mm tall

Configurations: side hung windows, top hung windows, fixed windows

Glass Specification: glass thickness up to 44mm, double glazing with low e coating and argon gas filling

Weather Protection: full testing completed, air (4), wind (2400 Pa), water (E1200)

top hung casement window with slim aluminium framing form sieger systems
large bedroom window with slim aluminium framing
multilight slim casement window configuration with fixed gable end windows
This slim aluminium window has a square edge detail on the profile and the glazing bead. By keeping the profiling minimal and square you create a clear edge to the glazing, making the opening look larger and clearer.

Even with such minimal profiles, the Sieger Slim casement window can still achieve impressive opening sizes with a side hung window available with a sash weight of 35kg and a top hung window available with a 50kg unit weight.

Fixed aluminium windows can be created with even larger sizes and this system is a great choice for large gable end windows or shaped openings for above any of our other aluminium door systems.

Thermal break technology is integrated into the framing profiles for integral thermal insulation. The system has been fully tested for weather, thermal and high levels of security. All of this comes together to offer you a slim aluminium window with impressive performance and modern styling.

See Them in The Showroom

There are multiple configurations of the Sieger Slim casement available to view at the Sieger showroom. Get in touch with a member of the team or click the link at the bottom of the page to book your appointment.

Get a Quotation

Request a quotation for your project by clicking the link below or just get in touch with a member of the team. All quotations for your aluminium window package are generated individually for your project to ensure you get the level of finish and performance you need.





Case Studies

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