Mallorca Villa Stephan Offermann minimal windows®

minimal windows

Open Living Concepts for Maximum Natural Light

Our double-glazed minimal windows® system is a virtually frameless, easy-to-operate aluminum sliding window system, with a greatly-reduced 21 mm leaf profile. The oversized sliding sections, up to 4 m in height, are set in virtually invisible frame profiles, allowing you to enjoy unobstructed views. Elevate your spirit with breath-taking sea views, twinkling city nightscapes, or natural landscapes and gardens.


Inviting the exterior into your living space, by using materials reduced to their bare essentials, is at the core of cutting-edge contemporary architecture! Clean lines, balanced proportions, drenched in the all-important and crucial central element, natural light. Whether it’s a luxury villa, a detached home, an apartment, or a business complex, unobstructed views with sweeping, open interiors allowing maximum natural light to illuminate the interior, are highly valued in current architectural design. Large glass fronts that adapt seamlessly to any environment, are flush with floor and ceiling. The sliding units operate with minimum resistance, made possible by the concealed tracks integrated into the floor, technology which took 15 years to perfect.

Key features & benefits
Rieteiland House Kumasol Netherlands minimal windows
Ultra-Slim Design, Countless Configurations

The virtually invisible fronts of the aluminum profiles emphasize the minimalistic design of Keller minimal windows®. The limitless system configurations and design options offer optimal practical flexibility, so you can select numerous options. Glass-to-glass interior and exterior corners, open corners, pivot elements, and wall-inlets (pockets in the brickwork) that conceal sliding elements. Select from a wide variety of colors, with an assortment of textured surfaces, from matt, to polished, to powder-coated.

Brussels Loft KMW Belgium minimal windows
Huge open and uncluttered glass surfaces

The frame profile is minimized to allow seamless integration into floors, ceilings and walls. Outer frames are almost completely integrated into walls, so oversized glass dimensions create wide, open living spaces. Maximum natural light infuses your interiors, creating a tranquil, elevated ambiance. Leaf sections can be as high as 4 m, with a total weight of up to 500kg. It allows us to create exceptional and expansive living environments, with sections installed on 1,2,3, or 4 tracks. We are proud to be able to fulfil the most extreme and ambitious architectural designs.

Straw House KMW Belgium minimal windows
Exceptional performance on every project

Choosing Keller minimal windows® means choosing the best possible quality. Our system’s insulation values are excellent. They maintain interior temperatures, delivering optimal conditions throughout the year. Polyamide bars integrated into the outer frame, guarantees thermal separation, which reduces energy consumption, saving on costs. In hot climates, cool air-conditioned air remains inside. Heat penetration can easily be prevented via the integration of foil which is impermeable to sunlight.

KMW minimal windows Exterior of Villa, Croatia
Seamless interior to exterior transition

Barely perceptible exterior frames, seamlessly integrated into the floor via a fitted sliding rail, ensure smooth, unobstructed transitions. High-performance tracks and rollers in stainless steel guarantee fluid manual functionality, high operational safety and superior durability. The transition from the interior to the exterior is effortless and seamless.

Villa Brussel KMW Belgium minimal windows
Fluid and effortless operation

Our exclusive, specially-developed locking and automation systems combine outstanding operational ease and security, with exceptional durability. Extremely powerful electric motors, with a tensile force of up to 2.400 kg, silently shift the sliding leaf sections. Various operational modes, such as room switch, remote-controlled, or a fully automated dead-man switch with laser sensors, may be selected, guaranteeing maximum operational ease.

Technical specifications
Profile facing width
21 mm
Maximum leaf height
4 m
Maximum leaf width
3 m
Thermal transmission coefficient
Uw ≥ 1,1 W/(m²K)
Maximum leaf area sliding
up to 8,5 m²
Maximum leaf area fix
up to 18 m²
Maximum leaf weight
500 kg
Overall insulation glass thickness
26 up to 34 mm
Automated sliding leaf
yes up to 2,400 kg
Unobstructed accessibility
DIN 18040-1, DIN 18040-2
Air permeability
Class 4 according to EN 12207
Rain resistance
Class 7A according to EN 12208
Wind load resistance
Class C4/B5 according to EN 12210
Sound insulation
Up to 39 dB according to ISO 717-1
Burglary protection
Up to WK2 (RC2) according to EN 1627
3D Minimal Windows Double Glazed Rendering
kmw download area computer screen rawpixel

Architects, planners and homeowners can take advantage of the wealth of design options made possible by our premium minimalist systems. Our engineers are exceptionally detail-oriented, paying attention to every single design element. We strive for perfection. Detailed technical information and drawings can be found on our download portal. Registration is free.



Need Project Advice?
Would you like to discuss a specific project, or would you like more information on Keller minimal windows®? We are happy to assist!