China Wholesale Aluminum Double Hung Windows Factory & Supplier

Enterprise Sourcing Advantages & Foshan Manufacturing Base

As a global leader in high-performance fenestration systems, Vexis Windows & Doors Co., Ltd. operates a 30,000 m² state-of-the-art intelligent manufacturing plant located in Lishui Town, Foshan City, Guangdong Province—the center of China's aluminum extrusion industry. Integrating architectural R&D, structural engineering, precision CNC fabrication, and direct international export, Vexis delivers factory-direct wholesale aluminum double hung windows and custom fenestration solutions to over 154 countries and regions across North America, Australia, Europe, and Asia-Pacific.

Unlike standard trading intermediaries or local assemblers, Vexis maintains total vertical control over profile extrusions, thermal strip insertion, glass tempering, double-glazing unit (IGU) assembly, hardware installation, and rigorous factory testing. Our technical department collaborates directly with foreign architects, project managers, and building materials importers to ensure every window unit conforms strictly to regional energy codes, structural wind load guidelines, and installation practices.

Engineering Architecture of Thermal Break Aluminum Double Hung Windows

Aluminum double hung windows represent the apex of traditional architectural aesthetics merged with modern materials engineering. Unlike single hung units where only the lower sash operates, double hung windows feature upper and lower sashes that glide vertically independently within a dual-track frame. This mechanical versatility maximizes continuous natural ventilation via convection: cool ambient air enters through the lower sash opening, while warmer interior air exits through the top sash opening.

1. Extruded Aluminum Alloy Profile Design (6063-T5 / T6)

Our aluminum double hung windows are engineered using prime structural-grade 6063-T5 and 6063-T6 aluminum alloys with nominal wall thicknesses ranging from 1.4 mm for standard residential units up to 2.2 mm for heavy-duty commercial curtain wall integration. The structural profile incorporates multi-chambered internal webbing, providing superior moment of inertia ($I_x$, $I_y$) against intense exterior wind pressures (DP50 to DP80 ratings).

2. Thermal Barrier Technology (Polyamide PA66 GF25)

Uninsulated aluminum frames exhibit high thermal conductivity ($k \approx 160\text{ W/m}\cdot\text{K}$), leading to thermal bridging, excessive energy loss, and interior surface condensation. To achieve superior U-factors, Vexis double hung windows feature mechanical crimped Polyamide PA66 GF25 (25% glass fiber reinforced) thermal break struts. This thermal barrier divides the exterior frame from the interior profile, lowering frame thermal conductance to under $2.0\text{ W/m}^2\cdot\text{K}$.

3. Heavy-Duty Constant-Force Torsion Spring Balances

Vertical operation relies on industrial-grade constant-force spiral balance or block-and-tackle spring counterbalance systems. Tested for over 50,000 continuous open-close cycles without tension degradation, these hardware balances allow sashes weighing up to 60 kg to slide effortlessly with less than 15 N of operating force. Furthermore, integrated tilt-in latches permit both sashes to pivot inward at 90 degrees for simple, safe glass cleaning from inside the building.

4. Multi-Layer Sealing & Water Management Systems

Weatherproofing is accomplished through continuous triple-layered EPDM (Ethylene Propylene Diene Monomer) gasket seals combined with high-density silicone-treated weather-stripping pile. The frame sill profile features a sloped drainage plane with concealed one-way weep hole valves, ensuring zero water pooling even under driving rains up to 700 Pa pressure.

Fenestration Technical Performance Specifications

Future Purchasing Trends in Global Aluminum Window Sourcing

The global fenestration industry is undergoing a structural paradigm shift driven by stringent municipal carbon-neutral mandates, rising energy costs, and evolving modern aesthetic preferences. Commercial developers, building owners, and wholesale importers sourcing aluminum double hung windows from China must align procurement strategies with five key technological trends over the next decade:

Vexis Windows remains at the forefront of these technological advancements, offering custom OEM/ODM extrusions, specialized low-emissivity glass coatings (Triple Silver Low-E), and complete compliance documentation for global buyers seeking long-term competitive advantages.

Factory Production Workflow & Quality Control Protocols

To guarantee zero-defect delivery across long-distance maritime freight, Vexis enforces strict quality control (QC) at every stage of the manufacturing pipeline within our Foshan facility:

• Raw Material Inspection: Chemical composition testing of raw aluminum billets via optical emission spectrometry to verify 6063-T5 alloy integrity.
• Thermal Break Insertion & Crimping: Automatic knurling and mechanical crimping of PA66 GF25 thermal strips, followed by shear force pull-testing.
• Surface Coating Excellence: Automated electrostatic powder coating (AkzoNobel / PPG certified) providing minimum 60-micron coating thickness, offering high resistance to salt spray, UV fading, and ocean breeze corrosion.
• IGU Glass Assembly: Dust-free cleanroom manufacturing of double/triple insulated glass units with automated robotic butyl sealing and gas-fill verification.
• Mock-up Pre-Assembly & Testing: Every custom order undergoes 100% pre-assembly in our workshop to test balance spring tension, locking mechanism alignment, and frame squareness before packing.
• Seaworthy Heavy Packaging: Finished windows are wrapped in 5-layer protective film, foam edge guards, shrink wrap, and packed inside fully enclosed steel-reinforced plywood crates to eliminate shipping damage.