ReynaersWindows & Doors

SlimLine 38

Steel-look minimalism. Maximum glass, minimal frame.

Classic - Application Example

Overview

What makes the SlimLine 38
stand out.

SlimLine 38 delivers the industrial steel-window aesthetic that architects love - with modern aluminum thermal performance. Nine configurations across four design variants (Classic, Ferro, Cubic, Functional), three insulation tiers (Standard, HI, HI+), plus fireproof and burglarproof editions. The new HI+ achieves Uw 0.74 with 100% recycled insulation bars and supports 3-meter sash heights. Ferro's sharp shadow-gap detailing replicates traditional steel windows. Glass fibre reinforced polyamide breaks (40 mm frame, 32 mm sash) deliver real thermal performance from a slim profile.

Learn more about thermally broken aluminum technology or compare European aluminum system providers.

Key Highlights

Nine configurations: 4 design variants x 3 insulation tiers + fire + security
HI+ achieves passive-level Uw 0.74 with 100% recycled insulation bars
Ferro: sharp shadow-gap steel-look for heritage and industrial projects
Cubic: robust stepped profile, 76 mm depth, modern squared aesthetic
Fireproof variant: EI2 30 / EW 30 rated (30-minute integrity)
Burglarproof: RC2, narrowest sightline at 56.5 mm

✓

Ideal For

Contemporary and industrial-style homes, loft conversions, heritage renovations with modern performance requirements, and interior glass partitions where the steel-look trend is key to the design intent.

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Consider an Alternative When

If the project calls for US-style outswing casements with interior screens, the SlimLine 68 Casement keeps a slim profile. In colder climate zones, specify the HI or HI+ tier with triple glazing - a double-glazed SlimLine 38 may not meet your energy code.

Technical specifications

Sightline (best)

2.22" (56.5 mm) - Burglarproof

U-Factor (best, HI+)

0.13 (Uw 0.74, triple glazing)

U-Factor (Classic HI, double)

0.26 (Uw 1.47)

U-Factor (Classic HI, triple)

0.16 (Uw 0.90)

Max Glazing

2.56" (65 mm) - Functional

Air Infiltration

Class 4 (EN 12207)

Water Resistance

Class 9A (600 Pa)

Wind Load

Class C4 (1,600 Pa)

Max Sash Height

9' 10" (3,000 mm) - HI+

Max Sash Weight

375 lbs (170 kg)

Design Variants

Classic, Ferro, Cubic, Functional

Insulation Tiers

Standard, HI, HI+

Projects using this system

Photographed on site.

SlimLine 38 installed on real builds - photographed during construction, before the cladding went on.

10 photos

Hill Road Residence

Residential - Luxury Custom Home - Greenwich, CT

Full fenestration package for a luxury custom build including main house and pool house. SlimLine 38 steel-look windows and folding doors connect indoor and outdoor living spaces. The schedule includes ConceptFolding 68 and a CF77 pool-house position.

View project

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