SlimLine 38 – High-Performance Aluminium Window System
SlimLine 38 is a high-performance aluminium window system designed for both inward- and outward-opening windows. It combines elegant design, everyday comfort, and excellent thermal insulation with a distinctive, minimalist appearance. Inspired by the look of narrow steel profiles, SlimLine 38 is an ideal solution for modern architecture.
The system is also perfectly suited for the renovation of buildings with original steel-framed windows. It allows architects and investors to preserve the authentic façade character while significantly improving thermal insulation and energy efficiency.
Minimalist Design Variants
SlimLine 38 is available in three refined aesthetic variants – Classic, Ferro, and Cubic – enabling precise adaptation to different architectural styles. Despite its slim profiles, the system supports both double and triple glazing, offering flexibility without compromising performance.
Designed for Contemporary Architecture
Thanks to its excellent thermal insulation parameters, SlimLine 38 meets the demanding requirements of modern architectural projects. It delivers a balanced combination of durable aluminium construction and minimalist, versatile design, making it a strong choice for both new buildings and renovation projects.

The SLIMLINE 38 system combines modern design with exceptional performance, offering superior thermal insulation, air tightness, and security features for a comfortable living environment.
Key features:
- Thermal insulation: Uf = 1.9 W/m²K, Uw = 0.96 W/m²K, ensuring excellent energy efficiency.
- Air tightness: Class 4 (600 Pa) for superior sealing.
- Water tightness: Class 9A (600 Pa) protects against water penetration.
- Wind load resistance: Class C4 (1600 Pa) designed to withstand strong winds.
- Burglar resistance: PAS 24-RC2 rated for enhanced security.
- Acoustic insulation: Up to 45 dB sound reduction, ensuring a quiet indoor environment.
- Height range: Min. 23.6 in. / Max. 9 ft. 10 in.
- Width range: Min. 17.7 in. / Max. 3 ft. 11 in.
- Maximum weight: 170 kg per unit for robust performance.
Benefits of Slimline 38:
- Energy Efficient: Excellent thermal insulation for lower heating and cooling costs.
- Weather Resistant: High resistance to wind, rain, and air infiltration.
- Secure and Quiet: High burglar resistance and soundproofing for enhanced comfort and safety.

SL 38 install guide
A comfortable home is one of the advantages from using the SlimLine 38 system. Thermal insulation and air infiltration are key parameters in maintaining a balanced climate inside.
The sleek appearance of the SlimLine 38 high-insulation system makes it an ideal choice for modern projects. Refined over time, these durable aluminum windows provide endless design possibilities with their numerous minimalist options.
- Slim steel-look design in a variety of styles
- Futureproof and durable window solution
- Crisp, high-quality finishing in every detail
Slimline – Modern Aluminum System with Narrow Profiles – YouTube
Why should you choose fix windows for your home? – Bertrand – Windows & Doors
PRODUCT OPTIONS
Personalise SlimLine 38 with the following options.
DIFFERENT STYLES
Unlimited design possibilities without compromise or impact on parameters.
