Thermafiber UltraBatt R-15 Mineral Wool Batts, 3.5" x 16" x 48" (24 Bags)

Dense, semi-rigid mineral wool batts deliver R-15 thermal performance with outstanding fire resistance and sound control. Sized for wood stud framing, these 3.5" x 16" x 48" batts install quickly and expand to a snug fit in exterior walls.

Key Features:

• High Thermal Performance: R-15 mineral wool batts help reduce energy loss in exterior walls
• Fire Resistance: Noncombustible insulation with ASTM C1338 compliance and 25 flame spread
• Sound Control: Dense fibers dampen noise between rooms and floors
• Easy Installation: Flexible batts cut with a serrated knife and expand to fill cavities
• Moisture & Mold Resistant: Noncorrosive, nondeteriorating material with minimum 70% recycled content

Please check the Product Data Sheet Here

Specifications Table:

Frequently Asked Questions (FAQ):

Q: What framing is this size intended for?
A: The 3.5" x 16" x 48" batts are designed for wood stud framing in exterior walls.

Q: How many batts come per bag and what is the coverage?
A: There are 5 batts per bag; the 3.5" x 16" x 48" size provides approximately 32 sq ft per bag.

Q: Can I cut the batts to fit around obstacles?
A: Yes. Use a serrated knife to measure, cut, and fit around boxes, pipes, or non-standard cavities.

Q: Is this insulation moisture or mold resistant?
A: Yes. UltraBatt mineral wool is moisture resistant, mold resistant, noncorrosive, and nondeteriorating.

Q: Does it help with soundproofing?
A: The dense, semi-rigid mineral wool fibers provide effective sound control between rooms and floors.

Elevate Comfort and Quiet with Sculpted Mineral Wool

This UltraBatt brings a tailored, architectural sensibility to your walls—clean, dense, and impeccably functional. Its mineral wool composition delivers a hushed serenity while bolstering thermal and fire protection. Pair it with refined wall finishes and natural woods to craft a space that feels cocooned and composed. A smart, luxurious foundation that lets design—and life—shine effortlessly.

Upgrade your walls with UltraBatt R-15 for efficient comfort, safer living, and quieter rooms—add to cart today.