PU Sealing Rock Mineral Wool
Fire resistance: Rock wool is made of minerals such as basalt and is a Class A non-combustible material. It can effectively prevent the spread of fire and improve building safety.
Thermal insulation: Rock wool has a low thermal conductivity, which can effectively reduce heat transfer, improve building insulation effect, and reduce energy consumption.
Sound insulation: The porous structure of rock wool can absorb sound waves and reduce noise transmission, and is suitable for places where sound insulation is required.
Corrosion resistance: Rock wool has stable chemical properties, is resistant to acid and alkali corrosion, is suitable for a variety of environments, and has a long service life.
High compressive strength: Rock wool has a tight structure and good compressive resistance, and is suitable for occasions that require load-bearing.
Product Introduction
Rock wool has significant advantages after being edge-sealed with polyurethane. In terms of fire prevention, rock wool is non-flammable, and when combined with treated polyurethane, it has a high overall fire prevention rating, ensuring building fire safety. It has excellent thermal insulation performance, and the low thermal conductivity of polyurethane works in synergy with rock wool to reduce heat loss and energy consumption. It has excellent sealing performance, and when solidified, it fits tightly to the edge of the rock wool, preventing air, water vapor and dust from invading, and extending the life of the board. At the same time, polyurethane edge sealing enhances the structural strength, making the board more resistant to external forces during transportation and use, and less prone to damage. Moreover, the board after edge sealing has a beautiful and neat appearance, with smooth lines, taking into account both practicality and beauty.
Product Specifications
Effective width | Wall panel: 950mm |
Roof panel: 960mm | |
Material | Color Steel Sheet |
Rock wool board | |
Structure | Upper and lower layer: color steel sheet |
Middle layer: Rock wool board | |
Thickness | Color steel sheet: 0.5~0.8mm |
Rock wool board: 50mm, 75mm, 100，150mm | |
Rock wool Density | 120kg/m³ |
Lifetime | 20~35 years |
Features | Heat Insulation, light weight, quick installation,waterproof, fireproof, soundproof, energy-saving,environmental friendly, |
Application Areas
Industrial plants: used for walls and roofs, providing insulation, fire protection, and sound insulation.
Warehouses: suitable for the walls and roofs of large warehouses to improve insulation effects.
Cold storage: used for cold storage walls, with excellent insulation performance.
Public buildings: such as gymnasiums, exhibition halls, etc., to meet fire protection and sound insulation requirements.
Temporary buildings: such as temporary buildings on construction sites, quick installation and reusable.
Lap Way
Sandwich panels can be overlapped in multiple ways. A seamless overlap with concealed nails creates a smooth and unblemished surface. The 20MM and 10MM seam overlaps, also featuring concealed nails, present varying degrees of joint visibility. Moreover, the tongue - and - groove overlap is highly favored as it guarantees a firm and snug connection between the panels.
PU Sealing Rock Mineral Wool refers to rock wool insulation panels or strips that are sealed with polyurethane (PU) resin to improve their dimensional stability, air-tightness, moisture resistance, and sealing capacity in fire-rated, thermally insulated, or acoustic construction systems. These sealed-edge or full-surface PU applications are especially useful in prefabricated panels, HVAC ducting, cleanrooms, and fire-resistant façades.
This article provides a detailed exploration of PU-sealed rock mineral wool—its composition, function, standards, use cases, installation protocols, and key advantages.
Table of Contents
What Is PU Sealing Rock Mineral Wool?
Technical Specifications and Material Properties
Engineering Applications and Use Scenarios
PU Sealing: Function and Benefits
Manufacturing Process and Material Composition
Regulatory and Industry Standards
Installation Guidelines and Safety Considerations
Frequently Asked Questions (FAQs)
Conclusion & Call to Action
1. What Is PU Sealing Rock Mineral Wool?
PU (polyurethane) sealing rock mineral wool refers to rigid or semi-rigid mineral wool boards or strips that are encapsulated, edge-sealed, or coated with polyurethane foam or resin. This sealing serves to:
Prevent fiber dispersion
Improve edge sealing against air, vapor, and water
Enhance adhesion to panel systems
Maintain core insulation performance in harsh environments
This system is widely used in high-performance building envelopes, prefab sandwich panels, and ventilation ducting where both insulation and airtight sealing are required.
2. Technical Specifications and Material Properties
| Property | Typical Value | Test Standard |
|---|---|---|
| Thermal Conductivity (λ) | 0.035–0.045 W/m·K | ASTM C518 / EN 12667 |
| Reaction to Fire (Core) | Euroclass A1 (Non-combustible) | EN 13501-1 |
| PU Sealing Density | ~30–60 kg/m³ (depending on application) | ISO 845 |
| Air Permeability (Sealed Edge) | ≤ 1.0 m³/h·m² under 50 Pa | EN 12114 |
| Compressive Strength | ≥ 60 kPa (rock wool core) | EN 826 |
| Water Absorption (24h partial) | < 1.0 kg/m² | EN 1609 |
| Edge Bond Strength | ≥ 0.1 MPa (PU-to-wool adhesion) | EN 1607 / EN 319 |
| Dimensional Stability | ≤ 1.5% (70 °C, 90% RH, 48h) | EN 1604 |
| VOC Emissions (PU) | Compliant with <0.5 mg/m³ | ISO 16000-9 / REACH |
3. Engineering Applications and Use Scenarios
PU-sealed rock wool solutions are ideal where thermal insulation, fire resistance, and edge-sealing integrity are required simultaneously:
➤ Sandwich Panels:
Used as core insulation in PU-faced or metal-faced sandwich panels for facades, cold rooms, and clean rooms.
➤ HVAC Ducting:
Sealed edges ensure air-tight joints, essential for pressurized ventilation systems.
➤ Curtain Wall Fire Stops:
PU-sealed mineral wool strips form intumescent or non-intumescent fire stops, maintaining compartmentation in buildings.
➤ Prefabricated Modules:
Provides dust control, clean edge finish, and ensures panel integrity during transport.
➤ Fire Doors and Partitions:
Used in core infills and seals where both mechanical strength and fire resistance are mandatory.
4. PU Sealing: Function and Benefits
| Function | Benefit |
|---|---|
| Air sealing | Prevents thermal loss and ensures energy efficiency |
| Edge reinforcement | Prevents compression and damage during handling |
| Dust/fiber containment | Ideal for cleanroom or sterile zones |
| Water resistance | Prevents water ingress at panel joints |
| Improved bonding surface | Enhances compatibility with adhesives, films, and lamination layers |
| Fire edge integrity | Seals joints against smoke and flame penetration (when paired with A1/A2-rated cores) |
5. Manufacturing Process and Material Composition
Core Material:
Rock Mineral Wool, made by melting basalt at ≥1450°C
Formed into fibers and bonded with thermosetting resin or formaldehyde-free binders
PU Sealing Process:
Edge/face sanding to ensure adhesion
PU foam (two-component) is injected, sprayed, or brushed along edges or surfaces
Foam is cured in ambient or controlled temperature
Optional coating, painting, or film lamination
Customization Options:
Color-coded PU (gray, white, black)
Fire-resistant PU sealants
UV-stabilized PU resin for outdoor panels
6. Regulatory and Industry Standards
| Standard / Regulation | Description |
|---|---|
| EN 13501-1 | Fire classification for building products (core must be A1, PU edge max B-s2,d0) |
| ISO 9001 / ISO 14001 | Manufacturer quality and environmental control systems |
| REACH / RoHS | PU formulation must not exceed allowable thresholds for heavy metals or hazardous VOCs |
| LEED / BREEAM | Credits available for energy efficiency and low-VOC materials |
| FM Approved (Optional) | Required for fire-tested panel assemblies in high-risk industrial buildings |
| GB 8624 (China) | Classifies PU rock wool panels in terms of flammability and smoke toxicity |
7. Installation Guidelines and Safety Considerations
Handling:
Wear gloves and respiratory protection when cutting unsealed wool.
Avoid excessive compression of PU-sealed edges during transport.
Fixing and Sealing:
Panels should be joined using interlocking systems or mechanical fasteners.
Sealed PU edges can be taped, foamed, or adhered for continuous vapor and air barrier.
Fire Safety:
For fire-stopping systems, use PU-encapsulated strips with tested performance, preferably certified to EN 1366-4 or ASTM E814.
Storage:
Protect from UV and moisture if PU seal is not coated or protected.
8. Frequently Asked Questions (FAQs)
Q1: Is the PU used in sealing flammable?
PU itself is organic and can be flammable; however, formulations with fire retardants or limited spread of flame additives are commonly used for compliance.
Q2: Can PU-sealed rock wool be used in exterior walls?
Yes, provided the PU seal is UV-protected or encased, and the system meets required fire ratings.
Q3: How is the PU seal tested for adhesion?
Through tensile or peel tests (EN 1607, EN 319), measuring the bond strength between PU and rock wool.
Q4: Is this suitable for cleanrooms or medical environments?
Yes, the sealed edges prevent fiber shedding, which is ideal for sterile or low-particle environments.
Q5: What thicknesses are available?
Typical thickness ranges from 25mm to 150mm, depending on insulation requirements and panel design.
9. Conclusion & Professional Call to Action
PU Sealing Rock Mineral Wool combines non-combustible insulation performance with sealed-edge durability, making it the material of choice for air-tight, fire-rated, and structurally stable building components.
If you're working on HVAC systems, modular wall panels, clean rooms, or high-rise façade systems, PU-sealed rock wool ensures:
Clean, safe edge finishes
Reduced energy loss through air infiltration
High fire-resistance and acoustic damping
Installation-ready, damage-resistant insulation elements
