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Improve Comfort with Rockwool RWA45 Insulation Slabs and Knauf APR Insulation Rolls


You might wonder why we mention Rockwool RWA45 insulation slabs and Knauf APR insulation rolls together. Despite being different products—RWA45 is a stone wool slab, while Knauf APR rolls are mineral wool insulation—they share many benefits that can enhance your building projects. In this blog post, we'll explore the advantages of both insulation types and why they are great choices for improving comfort in any space.

What is Rockwool RWA45?

Rockwool RWA45 is a high-density insulation slab made from natural stone wool that is renowned for its exceptional sound absorption and thermal insulation properties. The "RWA45" designation indicates its density, approximately 45 kg/m³ making it a top choice for enhancing building comfort.

Key Benefits of Rockwool RWA45 Insulation Slabs

  1. Exceptional Acoustic Insulation

Rockwool RWA45 is designed to significantly reduce noise levels due to its dense structure that traps sound waves, preventing them from travelling through walls, floors, and ceilings which makes it an excellent choice for:

  • Residential buildings: Ensuring quiet and peaceful living spaces.
  • Commercial offices: Reducing noise pollution for a more productive work environment.
  • Educational institutions: Creating a better learning atmosphere by minimising external noise.
  1. Superior Thermal Insulation

The high density of Rockwool RWA45 also provides outstanding thermal resistance by slowing down the transfer of heat resulting in:

  • Energy efficiency: Lower energy bills due to reduced reliance on heating and cooling systems.
  • Comfort: Consistent indoor temperatures throughout the year.
  • Environmental benefits: Reduced carbon footprint from decreased energy consumption.
  1. The versatility of 100mm Rockwool RWA45

Rockwool RWA45 is available in various thicknesses, including the popular 100mm RWA45. This thicker insulation slab offers enhanced acoustic and thermal performance, making it suitable for a wide range of applications, from residential homes to commercial buildings.


What are Knauf APR Insulation Rolls?

Knauf Acoustic Partition Rolls (APR) are made from glass mineral wool and designed to provide both acoustic and thermal insulation with flexible, lightweight, and easy-to-install properties, making them suitable for a wide range of applications.

Key Benefits of Knauf APR Insulation Rolls

  1. Effective Noise Reduction

Knauf APR insulation rolls are specifically designed to disrupt and absorb sound waves, reducing noise transmission through walls, floors, and ceilings, resulting in quieter indoor environments, making them ideal for:

  • Residential homes: Enhancing privacy and comfort.
  • Commercial buildings: Promoting a serene office atmosphere.
  • Healthcare facilities: Ensuring a peaceful environment for patient recovery.
  1. High Thermal Performance

The glass mineral wool composition of Knauf APR rolls traps air within its structure, providing excellent thermal insulation helping maintain stable indoor temperatures and improving overall energy efficiency.

Similarities Between Rockwool RWA45 Insulation Slabs and Knauf APR Insulation Rolls

  • Acoustic Insulation: Both products provide excellent sound absorption, making them ideal for reducing noise transmission in various building types.
  • Thermal Insulation: Both materials offer high levels of thermal resistance, helping to maintain consistent indoor temperatures and reduce energy bills.
  • Non-Combustibility: Both Rockwool RWA45 and Knauf APR are non-combustible, enhancing the safety of buildings.
  • Ease of Installation: These insulation materials are designed for straightforward installation and can be cut to fit various spaces.

Differences Between Rockwool RWA45 Insulation Slabs and Knauf APR Insulation Rolls

  1. Material Composition:

  • Rockwool RWA45: Made from natural stone wool, derived from volcanic rock. This results in a dense and robust structure.
  • Knauf APR: Made from glass mineral wool, composed of recycled glass and sand. This makes it lighter and more flexible compared to stone wool.
  1. Density and Acoustic Performance:

  • Rockwool RWA45: Known for its high density (approximately 45 kg/m³), contributing to its superior sound absorption capabilities. The dense structure of stone wool traps sound waves effectively.
  • Knauf APR: While effective at reducing noise, Knauf APR rolls have a lower density compared to Rockwool RWA45. This makes them slightly less effective in extreme noise reduction scenarios but still highly effective for general use.
  1. Moisture Resistance:

  • Rockwool RWA45: Highly resistant to moisture and does not absorb water, making it ideal for use in damp or humid conditions. It maintains its insulating properties even when exposed to moisture.
  • Knauf APR: Glass mineral wool can absorb moisture if not properly protected. A vapour barrier is recommended when installing Knauf APR rolls in areas prone to moisture to maintain their insulating performance.
  1. Environmental Impact:

  • Rockwool RWA45: Made from natural volcanic rock and recycled materials, which are abundant and sustainable. While the production process is energy-intensive, the material's durability and performance offer long-term environmental benefits.
  • Knauf APR: Produced using recycled glass and sand, with a lower energy requirement in manufacturing compared to stone wool. The use of recycled materials makes it a more environmentally friendly option.


Incorporating Rockwool RWA45 insulation slabs and Knauf APR insulation rolls into your building projects can significantly enhance both acoustic and thermal insulation as these products not only improve comfort and energy efficiency but also contribute to a quieter and safer environment. Whether you're working on residential, commercial, or industrial projects, choosing the right insulation products is crucial for achieving optimal results.