What Is Rock Wool Board? Manufacturing, Properties and Applications
Rock wool board (stone wool board) is a rigid thermal and acoustic insulation panel made from natural basalt rock. It is one of the most widely specified insulation materials for exterior walls, curtain walls, sandwich panels, and industrial applications because it combines A1 non-combustible fire performance with excellent thermal insulation.
How Is Rock Wool Board Made?
The manufacturing process starts with natural basalt — the same volcanic rock found in mountain ranges worldwide. The rock is melted in a cupola furnace at temperatures above 1450 °C, then spun into fine fibres. At Taishi, the fibres are laid down with a pendulum process that orients them into a uniform, dense web. A small amount of binder is added, and the web is cured and cut into boards of precise dimensions.
Taishi’s seven production bases give the company a combined capacity of 800,000 tonnes per year, allowing consistent supply for large export orders — from single containers to project-scale quantities.
Key Properties of Rock Wool Board
- Fire safety: A1 non-combustible, no flame spread, no significant smoke — meets the strictest building code requirements
- Thermal performance: Thermal conductivity ≤0.040 W/m·K (GB/T 25975-2018)
- High temperature resistance: Stable up to 750 °C, suitable for industrial insulation
- Water repellency: Hydrophobic treatment keeps performance stable in humid climates
- Acoustic absorption: Dense fibre structure reduces noise transmission
- Dimensional stability: Rigid boards that hold their shape under wind load and mechanical fixing
Common Applications
Exterior Wall Insulation (ETICS)
Rock wool boards of 50–120 kg/m³ are used in external thermal insulation composite systems. The 1200×600 mm format and 30–200 mm thickness range covers most facade specifications, with higher densities for high-rise wind-load resistance.
Curtain Wall Back Insulation
Denser boards (100 kg/m³ and above) provide the compressive strength and fire barrier required behind glass and metal curtain walls.
Sandwich Panels
Rock wool strips and boards form the non-combustible core of sandwich panels for cold storage rooms, clean rooms, and prefabricated buildings.
Industrial and Marine
High-temperature rock wool is used to insulate boilers, kilns, pipe systems, and marine engine rooms where temperatures exceed what organic insulation can survive.
Available Specifications
Standard rock wool boards from Taishi are available in:
- Sizes: 1200×600 mm (other sizes on request)
- Thickness: 30–200 mm
- Density: 50–120 kg/m³ in the exterior wall range; higher densities for industrial use
- Standard: GB/T 25975-2018; tests to EN 13162 and ASTM C612 available on request
Custom density, size, thickness, and facing (aluminium foil, mesh, kraft paper) are available for volume orders. See the full product range or send us your specification for a factory-direct quote.
Related reading
- Rock Wool Thermal Conductivity and R-Value Explained
- Rock Wool vs Fiberglass Insulation: Complete Comparison
- Rock Wool for Cold Storage and Sandwich Panels: Fire-Safe Insulation Guide
Buyer questions we get most
What densities is rock wool board made in?
Our range runs from 80 to 120 kg/m³ — felt and blanket at 100 kg/m³, pipe sections at 100 and 120 kg/m³, and denser boards where a panel core or a structural wall needs compressive strength.
Is rock wool board non-combustible?
Our rock wool is A1 non-combustible and tested to GB/T 25975-2018, which is why it is specified for fire-rated walls, pipework and marine applications rather than for cost alone.
How do I get a specification and a price?
Send the application, thickness and destination port. We reply within one working day with the specification and a factory-direct quotation, and samples can ship before you commit to a container.
About this guide
Who maintains it
This guide is maintained by the Taishi Rock Wool export team in Shandong, China — factory-direct rock wool and glass wool from seven production bases with a combined capacity of 800,000 tonnes a year. Technical questions go straight to the factory rather than to a trading desk: WhatsApp +86 175 6050 1246 or email cliu32626@gmail.com.
Standards and sources referenced
- GB/T 25975-2018 — Chinese national standard for rock wool and its products; our production and test reports follow it.
- EN 13162 — European product standard for mineral wool, including how thermal conductivity (λ) is declared.
- EN 13501-1 — fire classification of construction products; class A1 means non-combustible.
- ISO 8301 / ASTM C518 — steady-state thermal conductivity test methods behind any quoted λ figure.
- ASHRAE Handbook—Fundamentals — definitions of thermal conductivity and R-value used here.
- EURIMA — European Mineral Wool Manufacturers Association, technical guidance on mineral wool performance.
- Insulation Institute (NAIMA) — industry technical resources on insulation performance and specification.
Last updated: September 23, 2026