Delta Duct FD4 – Premium Insulated Flexible Duct

The Delta Duct FD4 is a superior-grade insulated flexible duct engineered for air conditioning, ventilation, and heating systems. Designed to deliver maximum thermal efficiency, air tightness, and installation flexibility, this duct is the perfect choice for high-performance HVAC applications in commercial, industrial, and residential environments.

Construction & Design

The Delta Duct FD4 features a robust multi-layer construction that ensures exceptional strength, insulation, and durability:

Inner Core: Double-layer aluminum/polyester laminate permanently bonded with flame-retardant adhesive to a high-tensile steel wire helix, ensuring airtightness and smooth airflow.
Insulation Layer: High-density glass wool insulation (available in 16, 24, or 32 kg/m³) provides outstanding thermal and acoustic performance.
Outer Jacket: Tough metalized polyester with a clear protective coating that resists tearing, corrosion, and aging.

Key Features

Superior Thermal Insulation – High-density fiberglass insulation minimizes heat gain or loss in HVAC systems.
High Airflow Efficiency – Smooth inner core reduces friction loss and maintains constant airflow.
Enhanced Durability – Multi-layer aluminum laminate and protective jacket resist mechanical damage and corrosion.
Fire-Resistant & Safe – Constructed with flame-retardant materials for added safety and compliance.
Noise Reduction – Insulation layer absorbs vibration and reduces system noise levels.
Easy Installation – Lightweight, flexible, and compatible with all standard duct fittings.
Maintenance-Free Operation – Resistant to mold, fungus, and microbial growth.

Technical Specifications

Diameter: 4” to 20”
Insulation Density: 16, 24, or 32 kg/m³
Insulation Thickness: 25 mm
Length: 25 feet
Maximum Velocity: 5000 FPM (25.5 m/s)
Maximum Positive Pressure: 10” W.C. (2.5 KPa)
Maximum Negative Pressure: ½” W.C. (0.12 KPa)
Insulation R-Value: 4.2 or 6 (F·hr/BTU)

Applications

The FD4 Insulated Flexible Duct is suitable for:

Air conditioning and ventilation ducts in commercial and residential buildings
Industrial HVAC systems, including factories and warehouses
Sound-sensitive environments like offices, hospitals, and theaters
Energy-efficient retrofit projects requiring flexible, insulated ducting solutions