PVC-steel Composite Frame Windows

When evaluating long-term window investments, PVC-steel composite frame systems offer a compelling fusion of thermal performance and structural resilience. The fusion of a multi-chamber uPVC profile with a galvanized steel reinforcement creates a sash that resists warping, air infiltration, and forced entry far better than conventional vinyl frames. Our catalog addresses diverse applications: Steel Reinforced PVC Composite Windows serve as the foundational rugged choice for high-traffic zones, while Tilt and Turn PVC-steel Composite Windows add dual-mode ventilation and effortless cleaning for modern living spaces. For single-family homes and multi-unit renovations, Residential PVC-steel Composite Windows deliver slim sightlines and low U-values that cut heating bills without sacrificing curb appeal. Large-scale projects benefit from Commercial PVC-steel Composite Windows, where uniform thermal breaks and heavy-duty hardware stand up to constant use and extreme weather. Every frame undergoes accelerated aging tests, salt spray corrosion checks, and repeated cycle testing to guarantee decades of reliable service in climates ranging from coastal salt air to freezing inland winters.


The PVC-steel Composite Frame Windows are engineered around a set of precision parameters that define their advantage across residential and commercial buildings. At their core lies a continuous 1.5 mm thick galvanized steel tube, fully encased in a high-impact, lead-free uPVC profile, creating a torsion-resistant frame that permits large glazing units without sag. The design incorporates three to six internal chambers for thermal damping and condensation control, and the proprietary welding at corners achieves a seamless bond that outperforms mechanically joined alternatives. Essential specification highlights include:

  • Frame depth variants: 60 mm (retrofit), 70 mm (standard), 80 mm (high insulation), and 88 mm (passive house certified).
  • Steel reinforcement: hot-dipped galvanized, interlocked at miters with TIG-welded joints, corrosion resistance exceeding ISO 9227 for 1,000 hours.
  • Glazing package: double glazing (5/16/4) with a 16 mm argon-filled cavity and dual low-E coating, or triple glazing (5/14/4/14/4) with warm edge Super Spacer technology.
  • Gaskets: co-extruded thermoplastic elastomer (TPE) middle seal and Q-Lon compression outer seal, tested to maintain elasticity down to -40°C.
  • Hardware suite: stainless steel tilt-and-turn gearing with crime-rated mushroom pins, anti-jemmy plates, and adjustable compression locks that achieve RC2 security level.
  • Surface finish: smooth white or woodgrain foil laminate in over 30 RAL shades, with optional aluminum cladding for enhanced UV reflection.

All systems undergo rigorous certification under EN 14351-1, and our quality management follows ISO 9001:2015. The table below captures the standardized performance data for an 80 mm frame equipped with triple glazing, representing our most specified configuration for low-energy and passive house projects.

ParameterSpecification DetailMeasured Value
Profile MaterialuPVC with 1.5 mm steel core, chloride-free formulationEN 12608 Class S
Frame Depth6-chamber PVC-steel hybrid80 mm (sash + outer frame)
Glazing MakeupTempered outer, laminated inner, dual Low-E5 mm toughened / 14 Ar / 4 mm / 14 Ar / 4.4.1 lam
Whole-Window U-valueW/m²K per NFRC 1000.82 (center pane 0.6)
Solar Heat Gain (g-value)Dependent on coating selection0.35 – 0.52
Sound Reduction IndexRw (C;Ctr) weighted40 (-2;-6) dB
Air PermeabilityEN 12207 classificationClass 4 @ 600 Pa
Water TightnessEN 12208 test pressureClass E1200 (1200 Pa)
Wind Load ResistanceDeflection limit L/300Class C5/B5
Sash OpeningInward tilt & turn, selectableTilt: 150 mm vent / Turn: 90° inward
Hardware DurabilityCycle endurance per EN 13126-825,000 full cycles
MaintenanceSelf-lubricating bearings, EPDM drainsAnnual cleaning recommended

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