minimal windows Spain

Systems - Materials and Properties

Keller minimal windows® has spent 15 years perfecting the development and manufacture of minimalist window and door systems.

We strive to combine optimal minimalistic design with maximum functionality. The concept of “less is more” has shaped contemporary residential architectural trends and been a significant inspiration for the development and design of our systems. Our aim is to offer system options that complement the spirit and design of your luxury living spaces.

Durability and smooth functionality are central characteristics which distinguish our system components and options. We developed a self-centering, integrated roller carriage to ensure superior sliding performance and silent operation. The roller carriage is concealed in the lower profile of the sliding leaf. Top-quality stainless-steel rollers ensure high load stability and smooth rolling performance, which is why our minimal windows® system is one of the best maintenance-free systems on the market. Find out all you need to know about our products’ properties and the materials we use for our systems.

Energy-Efficient Insulated Glass Panes

Choosing the most appropriate glazing for your requirements is an important decision when building your home. Our premium triple-glazed Keller minimal windows®4+ series contains three glass panes within one sealed frame. Each pane contains a pocket of inert gas, which is heavier than the surrounding air, making it an effective audio and temperature insulator. Our minimal windows®4+ systems deliver excellent energy efficiency and are well-suited to installation in low-energy and passive houses.

villa neo stolwarker minimal windows and highline


Our multi-point locking system offers exceptional defense against burglary. It has been certified in accordance with burglary defense class RC 2. minimal windows® sliding systems are custom- designed to our customers’ preferences and installation requirements. A range of products such as linear actuators, locking monitors with magnetic contacts, and security sensors, are optional. Our products are compatible with a wide range of security accessories to ensure optimal security.

villa neo stolwarker minimal windows and highline

Stainless-Steel Sliding Rail and Roller Carriage

Our stainless-steel sliding rail, recessed at the lower end of the outer frame, guarantees superior sliding performance and silent operation of transparent sliding elements. It is entirely maintenance-free. The overlying roller carriages fit perfectly, matching the sliding rails.

The self-centering integrated stainless-steel roller carriages are concealed in the lower profile of the sliding elements.  The operating system is designed to minimize resistance caused by dirt or dust. The high-quality stainless-steel rollers ensure superior load stability and smooth operation of sliding sections weighing up to 1000 kg.

Amit Geron minimal windows

Wall Pockets

Our wall pockets allow all the sliding sections to disappear into the wall. Automated or manual operation enables the minimal windows® sliding elements to slot into specifically-constructed wall pockets, making the room appear even larger, making the glass panes imperceptible.

Systems Wall Pockets

No Corner Posts

To create the contemporary light-infused, sweeping architectural style, wide open spaces and flexibility are key. The Keller minimal windows® system makes it possible to create extraordinary, flowing interior-to-exterior living spaces. Another feature that achieves this look and feel is our open corner technology. Open corners are an extremely effective way to create imposing, sweeping interiors. Our unique frame profile attaches smoothly to the end of a sliding leaf, allowing the adjacent sash to slide in seamlessly at a 90-degree angle.

millbrook iq uk minimal windows open corner

Fitted Flush-to-Floor

The entire perimeter of the outer frame can be recessed into walls, ceilings and floors. When open, a no-threshold transition from interiors to the exteriors is created. The integrated stainless steel sliding rail is level with the floor, with no transitional elements protruding. It is also completely maintenance-free.

munArchitecten Marc Sourbron minimal windows Belgium

No Transitional Obstruction

The flush-to-floor minimal windows® freeway sliding rail guarantees smooth, obstacle-free accessibility, due to doorways being threshold-free. The outer frame is perfectly integrated into the floor, and because the sliding rail is level with the floor, you never stumble over bothersome barriers. The Freeway system is tested, certified and completely maintenance-free.

Systems freeway


Effective drainage is achieved via a specially-designed, integrated PVC hollow chamber. This drainage profile is fitted below the lower end of the aluminum frame.

Another option is a concealed drainage gutter with stainless-steel covers. No matter which minimal windows® system is installed, or which multiple systems have been jointly configured, the drainage always adapts perfectly, guaranteeing reliable water run-off.

house l livingglas austria minimal windows 4+
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