What is the difference between Rockwool and Owens Corning Thermafiber Fire and Sound Guard Plus Mineral Wool Insulation?

When choosing mineral wool insulation, two popular options often come up: Rockwool and Owens Corning Thermafiber Fire and Sound Guard Plus. Both products offer fire resistance and soundproofing benefits, but they differ in composition, performance, and applications. Understanding these differences can help homeowners, builders, and contractors make informed decisions for their insulation needs.

Close-up of mineral wool insulation batts

What is Rockwool Insulation?

Rockwool, also known as stone wool, is made by melting natural volcanic rock and spinning it into fibers. This process creates a dense, fibrous material that traps air, providing excellent thermal insulation and sound absorption. Rockwool is widely used in residential and commercial construction for walls, ceilings, and floors.

Key Features of Rockwool

• Fire resistance: Rockwool can withstand temperatures above 1,000°C (1,832°F), making it highly fire-resistant.

• Soundproofing: Its dense fibers absorb sound waves, reducing noise transmission.

• Water resistance: Rockwool repels water but allows moisture vapor to pass through, preventing mold growth.

• Durability: It does not settle or degrade over time, maintaining its insulating properties.

• Eco-friendly: Made from natural rock and recycled materials, Rockwool is sustainable and recyclable.

  
  

What is Owens Corning Thermafiber Fire and Sound Guard Plus?

Owens Corning Thermafiber Fire and Sound Guard Plus is a type of mineral wool insulation designed specifically for fire protection and sound control. It is manufactured by melting basalt rock and recycled slag, then spun into fibers. This product targets commercial and residential applications where fire safety and noise reduction are priorities.

Key Features of Thermafiber Fire and Sound Guard Plus

• Fire protection: It provides up to 2 hours of fire resistance, meeting strict building codes.

• Sound control: Designed to reduce sound transmission in walls and ceilings.

• Lightweight: Easier to handle and install compared to some other mineral wool products.

• Moisture resistance: Resists water absorption and helps prevent mold.

• Versatility: Available in batts and boards for different construction needs.

  
  

Thermafiber Fire and Sound Guard Plus insulation in wall cavity

Comparing Composition and Manufacturing

Both Rockwool and Thermafiber are mineral wool products made from natural rock materials, but their raw materials and manufacturing processes differ slightly:

• Rockwool uses primarily volcanic rock, which gives it a heavier and denser structure.

• Thermafiber combines basalt rock with recycled slag, resulting in a lighter, more flexible product.

  
  

This difference affects handling, installation, and performance in specific applications.

Performance Differences

Fire Resistance

Both products offer excellent fire resistance, but Thermafiber Fire and Sound Guard Plus is specifically tested and rated for up to 2 hours of fire protection in wall and floor assemblies. Rockwool also performs well in fire tests but may vary depending on the product line.

Soundproofing

Rockwool’s dense fibers provide superior sound absorption, making it a favorite for soundproofing studios, theaters, and homes. Thermafiber also reduces noise effectively but is optimized for combined fire and sound applications.

Thermal Insulation

Both insulations provide good thermal resistance (R-value), but Rockwool’s higher density can offer slightly better thermal performance in some cases. Thermafiber balances thermal insulation with fire and sound control.

Installation and Handling

Thermafiber Fire and Sound Guard Plus is lighter and easier to cut, which can speed up installation. Rockwool’s density makes it more rigid but also more durable once installed. Both products are non-combustible and safe to handle with proper protective gear.

Environmental Impact

Both products are environmentally friendly options compared to fiberglass or foam insulation. They use natural and recycled materials and do not off-gas harmful chemicals. Rockwool’s heavier weight means more energy is used in transportation, but it is highly recyclable.

Choosing the Right Insulation for Your Project

• For fire-rated assemblies: Thermafiber Fire and Sound Guard Plus is a strong choice with tested fire ratings.

• For soundproofing: Rockwool’s density makes it ideal for noise reduction.

• For thermal insulation: Both perform well, but Rockwool may edge out slightly in colder climates.

• For ease of installation: Thermafiber’s lighter weight can reduce labor time.

• For sustainability: Both are eco-friendly, but check local availability and recycling options.

  
  

Final Thoughts

Rockwool and Owens Corning Thermafiber Fire and Sound Guard Plus mineral wool insulation both offer excellent fire resistance, soundproofing, and thermal benefits. The choice depends on your specific project needs, budget, and installation preferences. Understanding their differences helps ensure you select the right insulation that balances safety, comfort, and efficiency.

Consider consulting with insulation professionals or suppliers to get samples and technical data for your project. Proper installation is key to maximizing the benefits of either product.