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

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
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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.