JM (Johns Manville) SAFB Unfaced Mineral Wool Batt Insulation R-3.7, 24 in x 48 in x 2 in, 112 sq ft Bag (MW224-A)
Regular price $81.32Unfaced mineral wool batt insulation (24 in x 48 in)
JM SAFB unfaced mineral wool batts are designed to help reduce noise transmission in wall and ceiling cavities while providing durable, noncombustible insulation. Ideal for metal-stud partitions, exterior walls, and above suspended ceilings, each bag covers 112 sq ft.
Key Features:
- Sound Attenuation: Absorbs sound and can improve wall assembly STC ratings by up to 10 dB
- Fire-Resistant Mineral Wool: Melting point in excess of 2000°F; Flame Spread 0 and Smoke Developed 0 (per listed testing)
- Unfaced Batts: Fits into cavities without a facing, making it easy to pair with separate vapor/air control layers as needed
- Moisture/Mold & Pest Resistant: Inorganic fibers resist fungi growth and do not sustain vermin
- Bulk Coverage: 112 sq ft per bag with 14 batts per bag for efficient installation on larger areas
Please check the Product Data Sheet Here
Specifications Table:
| Specification | Details |
|---|---|
| Product name | R-3.7, 24 in x 48 in, Unfaced, Mineral Wool Batt Insulation, 112 sq-ft |
| Brand | JM |
| Category | Batt Insulation |
| Material | Mineral Wool |
| Facing | Unfaced |
| R-Value | R-3.7 |
| Width | 24 in |
| Length | 48 in |
| Thickness | 2 in |
| Coverage area | 112 sq ft per bag |
| Pieces per package | 14 pieces per bag |
| Sound control | Improves wall assembly STC ratings by up to 10 dB |
| Fire resistance | Melting point in excess of 2000°F (1093°C); Flame Spread 0; Smoke Developed 0 |
| Durability | No growth of fungi; no sustaining of vermin |
| Thermal resistance test method | ASTM C518 |
| Flame spread/smoke development test method | ASTM E84 |
| Critical radiant flux test method | ASTM E970 |
| Water vapor sorption test method | ASTM C1104 |
| Odor emission test method | ASTM C1304 |
| Fungi resistance test method | ASTM C1338 |
| Combustion characteristics test method | ASTM E136 |
Frequently Asked Questions (FAQ):
Q: Where can this insulation be used?
A: It’s intended for metal-stud wall cavities in interior partitions and exterior walls, and for use above suspended ceiling systems for sound control.
Q: Is it faced or does it include a vapor barrier?
A: No—this product is unfaced, so it does not include an integrated vapor retarder.
Q: How much area does one bag cover?
A: One bag covers 112 sq ft and includes 14 batts.
Q: What are the batt dimensions and thickness?
A: Each batt is 24 in wide x 48 in long x 2 in thick.
Q: What makes mineral wool a good choice for sound and fire performance?
A: The listed SAFB mineral wool batts provide strong sound absorption and are described as fire-resistant with a melting point above 2000°F and Flame Spread/Smoke Developed ratings of 0.
Quiet confidence, built into the walls
There’s a certain luxury in spaces that feel hushed and composed—this unfaced mineral wool batt brings that calm behind the scenes. Designed for sound attenuation and strong fire performance, it elevates interiors by making rooms feel more private, intentional, and serene. Use it in media rooms, bedrooms, or between lively living spaces and work zones to sharpen the architecture’s sense of control. It’s the kind of invisible upgrade that makes a home feel impeccably considered.
Upgrade your walls and ceilings with JM SAFB mineral wool batts for quieter, more resilient spaces—add a bag to your project today.
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