ROCKWOOL Plus™ MB
ROCKWOOL Plus™ MB is a stone wool insulation batt designed for use in pre-engineered metal building constructions where an hourly fire rating is not required.
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Popular applications
- Metal building insulation
About this product
ROCKWOOL Plus™ MB is a lightweight stone wool batt insulation designed for pre-engineered metal building construction where an hourly fire rating is not required.
Noncombustible and fire resistant, Plus MB will not produce toxic smoke or promote flame spread, adding a layer of protection to wall assemblies.
ROCKWOOL Plus MB also helps to increase energy efficiency and improve thermal stability. Strong and durable onsite, it is easy to cut and install.
- Noncombustible and fire resistant
- Water and moisture repellent
- Excellent acoustic performance
- Inorganic, does not promote mold growth
- Dimensional stability to maintain performance
Why use stone wool insulation
- Noncombustible and fire resistant, stone wool works to contain a fire and prevent its spread.
- Stone wool provides excellent noise reduction and sound absorption to help you create quieter, more productive environments.
- Excellent thermal performance providing a high R-value per inch
- Durable inorganic material that does not rot or promote the growth of mildew, fungi or bacteria
Applications
- Designed for pre-engineered metal building (PEMB) construction
- Used in assemblies without an hourly fire rating
- Installed between girts and purlins in secondary framing
- Commonly installed with adhered insulation pins
Product certificates
UL Classified - CA/USA
ROCKWOOL Plus™ MB sizes, dimensions & packaging
Find ROCKWOOL Plus™ thickness, width, length and pack quantities—everything you need for accurate specification and ordering.
- All
- 8
- 12
- 14
- 16
- 20
- 24
- All
- 2
- 3
- 3.5
- 4
- 5
- 6
Specifications & testing
Explore ROCKWOOL Plus™ MB specifications and test results, based on relevant industry standards.
| Name | Value | Unit | Test standard |
|---|---|---|---|
| Mineral Fiber Thermal Insulation for Buildings | Type 1 Compliant | CAN/ULC S702 | |
| Mineral Fiber Blanket Thermal Insulation | Type III Compliant | ASTM C553 | |
| Flame spread index | 0 | ASTM E84 | |
| Smoke Developed Index | 0 | ASTM E84 | |
| Combustibility of Materials at 750 °C | Non-combustible | ASTM E136 | |
| Determination of Non Combustibility of Building Materials | Non-combustible | CAN/ULC S114 | |
| Corrosion of Steel | Passed | ASTM C665 | |
| R-Value / inch @ 75 °F | 4 | hr.ft².F/Btu | ASTM C518 (C177) |
| RSI value / 25.4 mm @ 24 °C | 0.7 | m²K/W | ASTM C518 (C177) |
| Determination of Fungi Resistance | Passed | ASTM C1338 |
ROCKWOOL Plus™ MB technical documents & resources
Download ROCKWOOL Plus™ MB technical documents and resources, including the product data sheet, to support accurate specification and efficient project planning.
ROCKWOOL Plus MB batt insulation for metal buildings - Data sheet
ROCKWOOL Plus™ MB is a lightweight, stone wool batt insulation designed for pre-engineered metal building construction where an hourly fire rating is not required.
Exterior stone wool wall insulation for pre-engineered metal buildings
This bulletin offers a detailed overview of ROCKWOOL stone wool insulation tailored for pre-engineered metal buildings (PEMBs). It outlines the significant advantages of ROCKWOOL products, such as enhanced thermal performance, increased energy efficiency, and superior fire resistance. Additionally, the bulletin explores various insulation strategies and highlights the importance of proper water, air, and vapor control layers in PEMBs.
ROXUL Safe 55 & 65 and ROCKWOOL Plus MB insulation for pre-engineered metal buildings
Stone wool insulation for exterior and interior steel-faced firewall applications. ROXUL Safe 55 and 65 products and solutions for tested and approved 1- and 2-hour fire-rated systems.
Guidelines for cutting stone wool insulation
Properly cutting stone wool insulation ensures fit and maintains performance, preventing safety and efficacy issues.
Related products
Explore more stone wool insulation solutions for similar applications.
Exterior wall
ROXUL Safe® 55 & 65
ROCKWOOL ROXUL Safe® 55 & 65 are stone wool insulation boards approved for use in metal building assemblies where a 1- or 2-hour fire resistance rating is required from one side or both sides of the wall.
Attend a ROCKonnect Masterclass
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Product support & insights
From expert technical guidance to real-world case studies and certified sustainability documents, access the tools and insights that support confident, high-performance building with stone wool insulation.
Speak to an expert
Contact our technical team for product, application, and building science support on stone wool insulation.
View our case studies
Discover some of our case studies to learn more about applications of our products in various projects across North America.
Access sustainability documentation
Explore ROCKWOOL’s certified products for transparency and sustainability, including EPDs, HPDs, GREENGUARD, and Declare labels.
