Brief Description:Fire-resistant rock wool board for insulated metal ventilation ductwork is Euroclass A1 non-combustible black rock wool with a melting point of 1000C. Developed for smoke extract and HVAC duct fire cladding, anti-shrink, vibration-resistant and moisture-proof. Custom density and thickness for commercial and industrial HVAC fire safety projects.

Fire‑Resistant Rock‑wool Board for Insulated Metal Ventilation Ductwork is a Euroclass A1 non-combustible fire-proof insulation board developed specifically for Insulated Metal Ventilation Ductwork, including metal ventilation ducts, smoke-extract ducts and air-supply HVAC duct systems. Adopting an exclusive high-melting-point black rock-wool formulation and manufacturing process, it serves as an upgraded alternative to conventional yellow rock-wool. The board effectively addresses frequent on-site issues including high-temperature shrinkage, flue-gas leakage, poor thermal performance, panel delamination and performance failure caused by moisture. Widely used in HVAC fire-safety projects such as commercial complexes, office blocks, hospitals, underground car parks and industrial plants, all product indicators comply with smoke-ventilation codes and acceptance criteria for thermal and fire-resistant ventilation ductwork.

1. Product Overview

As the dedicated cladding material for Insulated Metal Ventilation Ductwork, this fire-resistant rock-wool board is fitted onto galvanised-steel metal ducts to deliver core functions of thermal insulation, fire resistance and noise reduction. An external protective cladding layer can be applied on request, forming a composite ventilation-duct system integrating fire resistance, thermal insulation, sound absorption, moisture-proofing and anti-corrosion. Compared with standard insulated duct systems, this solution features superior fire-resistance stability and enhanced high-temperature tolerance. It resists cracking and hollowing under long-term airflow vibration and represents a well-established compliant solution for smoke-extract, pressurised air-supply and central-air-conditioning ventilation projects.

2. Core Material Advantages (Haochen Fire-Resistant Black Rock-wool Board)

The duct-specific black fire-resistant rock-wool board is produced from basalt and other high-melting-point mineral raw materials through high-temperature melting, fibre spinning and high-pressure curing. It exhibits a natural dark-brown finish with no artificial dyeing, is asbestos-free and environmentally safe. Its custom-blended mineral formula raises fibre temperature-resistance thresholds and overall structural strength, optimised for real-world operating conditions including sustained wind-pressure impact, intense flue-gas heating and damp ceiling environments within metal duct installations. Classified Euroclass A1 non-combustible, the board generates no flame spread, no molten drips and no toxic fumes during fire exposure, effectively restraining flame and flue-gas propagation along duct runs. With a melting point reaching 1000 °C, it undergoes minimal thermal deformation without shrinkage or collapse under high-temperature conditions. It preserves the integrity of duct fire-resistant cladding and consistently meets engineering requirements for 1.0 h, 1.5 h and 2.0 h fire-resistance durations.

3. Thermal Insulation and Energy-saving Performance

Boasting low thermal conductivity and outstanding insulating properties, the black rock-wool board fitted externally to Insulated Metal Ventilation Ductwork efficiently blocks heat transfer across duct walls. When applied to air-supply ducts, it reduces heating and cooling energy losses, eliminates condensation dripping on duct surfaces and improves the energy efficiency of HVAC systems. For smoke-extract duct applications, it contains outward heat radiation, prevents ignition of ceiling-mounted cables and panels, mitigates fire risks and enhances the operational stability of whole-building ventilation networks.

4. Sound Absorption and Optimised Ventilation Performance

Featuring a porous inorganic-fibre internal structure, the board delivers excellent sound-absorbing capability. It effectively attenuates vibration-borne noise from fans and airflow-friction noise within ductwork. Installed in plant-room ductwork, ceiling-mounted ventilation lines and supply-and-extract ducting for underground car parks, it substantially lowers operational noise of ventilation systems, satisfies building acoustic-design standards and improves environmental conditions in plant rooms and public zones.

5. Vibration-resistant Durability, Moisture-proof and Anti-corrosion Properties

Manufactured via high-density compression, the high-melting-point black rock-wool board features tightly interlocked fibres and robust monolithic construction. It withstands wind-pressure fluctuations and airflow vibration from frequent metal-duct cycling. No delamination, fibre shedding or hollowing occurs throughout long-term service, extending service life for concealed installations. Subjected to full water-repellent treatment, the board shows extremely low moisture absorption. Even in humid conditions such as underground utility corridors and enclosed damp ceiling voids, it resists water ingress, mould and decay and will not corrode outer surfaces of galvanised-steel ductwork, prolonging the service life of the complete ventilation-duct system.

6. Upgrade Benefits versus Conventional Yellow Rock-wool

Standard yellow rock-wool offers limited heat resistance with a melting point of only 700 °C. Under smoke-duct high-temperature exposure it tends to soften, shrink and crack, damaging fire-resistant cladding and enabling flue-gas leakage, which fails high-level smoke-ventilation fire-resistance requirements. Its relatively soft texture makes it prone to dislodgement under persistent airflow vibration, and performance degrades significantly upon moisture exposure. Purpose-engineered for duct fire-safety service conditions, the black high-melting-point rock-wool board brings comprehensive improvements in high-temperature resistance, anti-shrink performance, vibration resistance and moisture tolerance. It delivers stable fire-resistance ratings, achieves high-quality finished installations and requires virtually no post-installation maintenance. As a preferred upgraded material for fire-resistant thermal cladding of Insulated Metal Ventilation Ductwork, it supports higher project fire-inspection pass rates.

7. Main Application Scenarios

• Fire-resistant thermal cladding for metal smoke-extract ducts, pressurised air-supply ducts and make-up-air ducts in diverse building types

• Thermal-insulation and noise-reduction treatment for central-HVAC supply-return air ducts

• Thermal and acoustic insulation for ductwork within fan-rooms and air-handling-plant rooms

• Supplementary fire-stopping for duct penetrations through walls, floor slabs and fire-compartment boundaries

• Long-term protective treatment for ventilation ductwork inside underground utility corridors and high-humidity zones

Suitable for new-build and refurbishment HVAC fire-safety projects.

8. Manufacturer Strength & Project Support

With extensive experience in duct-focused fire-resistant thermal-insulation materials, Haochen Insulation specialises in fire-resistant rock-wool boards for Insulated Metal Ventilation Ductwork. Stocked standard density grades include 120 kg/m³ and 140 kg/m³. Beyond standard stock sizes, custom-manufacturing of board density and thickness is available according to project-specific operating conditions and fire-resistance design requirements, flexibly matching varying duct dimensions, fire-resistance durations and on-site installation constraints. The factory supports large-volume supply for nationwide construction projects with stable stock availability, providing one-stop material-selection solutions for fire-resistant thermal cladding of metal ventilation ductwork.