Rockwool Insulation Acoustic Slab

What Is Rockwool Insulation?

Rockwool is a globally recognised leader in the production of rock mineral wool insulation. Their products are made from natural volcanic rocks, primarily basalt and diabase, which are melted at high temperatures and spun into fine fibres. This process creates a dense yet porous material that excels in thermal, acoustic, and fire-resistant performance. 

At the core of Rockwool’s offerings are insulation solutions that improve energy efficiency, comfort, and safety in both residential and commercial buildings. With a thermal conductivity range of 0.034 - 0.040 W/mK, their products reduce heat transfer, leading to lower energy consumption and more consistent, comfortable indoor temperatures year-round.

Beyond thermal insulation, Rockwool is also highly effective at soundproofing. Its fibrous structure absorbs sound, reducing noise transmission between rooms, floors, and walls, making it ideal for creating quieter, more peaceful spaces.

Another key benefit of Rockwool is its fire resistance. As a naturally non-combustible material, Rockwool can withstand temperatures up to 1000°C without compromising its structural integrity. This makes it a crucial component for enhancing fire safety in buildings. In the event of a fire, its use helps slow the spread of flames, providing valuable time for evacuation and reducing the risk of structural damage.

At Materials Market, we sell a vast range of Rockwool insulation products, including: 

• Rockwool Flexi Slab
• Rockwool RW3 Slab
• Rockwool RW5 Slab
• Rockwool RWA45 Slab
• Rockwool Rainscreen Duo Slab

Applications

Due to the rigid, semi-rigid, and flexible properties of stone wool, Rockwool slabs provide outstanding thermal and acoustic insulation for internal walls and floors. These versatile slabs can easily be installed in partition walls, whether constructed from brick, concrete, timber frame, or other base materials.

Rockwool is also highly effective at soundproofing between floors, reducing noise transmission across walls, roofs, and floors, and providing comprehensive insulation throughout a building.

In addition to its insulation properties, stone wool is water-repellent while allowing water vapour to pass through. This makes the slabs ideal for areas such as ceilings and basements, where moisture and damp could otherwise pose problems.

The slabs can be used within:

• Interior timber or steel partition walls
• Interior timber frame floors
• Interior timber frame ceilings
• Pitched roofs
• Acoustic ceilings and partition panels
• I-joist interior partitions
• Party walls

Key Features 

• Thermal Insulation: It offers excellent heat resistance, helping to maintain indoor temperatures and improve energy efficiency by reducing heat transfer.
• Acoustic Insulation: The dense, fibrous structure of Rockwool helps absorb sound, making it an effective solution for reducing noise transmission between rooms, floors, and walls.
• Fire Resistance: Rockwool is naturally non-combustible and has a high melting point, which makes it an effective fire barrier, slowing the spread of flames in case of a fire.
• Sustainability: Made from abundant natural materials, it is recyclable and contributes to energy-efficient and sustainable building practices.
• Moisture Resistance: It does not absorb water, which means it maintains its insulating properties even in damp conditions.

Rockwool: Thermal Conductivity & Thickness Recommendations

Rockwool Insulation Thermal Conductivity (λ): 0.034 – 0.040 W/mK

The following thicknesses are recommended based on thermal conductivity to meet specific U-values (overall heat transfer coefficient) for various building applications.

The thickness recommendations and U-value guidelines provided are based on general industry standards and Rockwool’s performance data. However, individual building requirements may vary depending on specific project conditions, local regulations, and other factors. 

We strongly advise customers to consult with a qualified professional or building expert to ensure that the selected insulation meets all relevant building codes and performance requirements for your particular application.

Existing Elements

• Roofs: To achieve a U-value of 0.16 W/m²K, use 120-130mm of Rockwool.
• Walls: To achieve a U-value of 0.30 W/m²K, use 110mm of Rockwool.
• Floors: To achieve a U-value of 0.25 W/m²K, use 110-120mm of Rockwool.

Renovations/New Elements in Existing Dwellings

• Roofs: To achieve a U-value of 0.15 W/m²K, use 260-290mm of Rockwool.
• Walls/Floors: Similar to new builds, use 150-170mm for walls and 190-220mm for floors to meet the 0.18 W/m²K U-value.

New Builds

• Roofs: To achieve a U-value of 0.11 W/m²K, use 230-260mm of Rockwool.
• Walls: To achieve a U-value of 0.18 W/m²K, use 150-170mm of Rockwool.
• Floors: To achieve a U-value of 0.13 W/m²K, use 190-220mm of Rockwool.