R-49 labeled performance in a 14 in. thick unfaced batt
Key features
24 in. width for full-bay coverage on 24 in. o.c. ceilings
PINK Next Gen handling with improved recovery after compression packaging
Technical specifications
| R-Value | 49.0 |
|---|---|
| Thickness | 14.0 in |
| Width | 24.0 in |
| Length | 48.0 in |
| Coverage | 48.0 sq ft/pack |
| Material | Fiberglass (PINK Next Gen), unfaced |
| Fire rating | ASTM C665; unfaced glass fibers classified noncombustible per ASTM E136 in manufacturer documentation. Unfaced PINK Next Gen acceptable ICC types I–V per OC literature. |
| Sound rating | Thick cavity fill improves impact and airborne metrics versus bare joists; final results depend on ceiling finish and penetrations. |
| Density | Light-density flexible batt per ASTM C665 manufacturer listings; see TDS for product-specific values. |
| Thermal conductivity | Labeled R-49 at stated thickness; see manufacturer TDS (ASTM C518) for tested conductivity. |
| Framing width | 24 in. width for 24 in. on-center joist or truss bottom chord spacing |
| Construction type | Wood-frame and light-gauge metal-frame cavity construction |
| Application area | Wood- and metal-framed walls, floors, roof/ceilings; interior side of basement and unvented crawlspace walls per code and OC literature. |
Product details
About 48 square feet per package (IDI-listed coverage). Primary use: attic floors, flat ceilings, and compatible roof assemblies where aggressive R-49 targets meet 24 in. on-center framing modules.
Cold-climate energy codes and deep retrofit programs often push attic R-values into the high forties. BU92 answers with a single-layer unfaced batt geometry: 24 in. width matches the common 22-1/2 in. clear span for 24 in. stud or joist spacing, 48 in. length matches four-foot material staging, and 14 in. labeled thickness is the published R-49 thickness in Owens Corning’s PINK Next Gen availability tables. That combination is heavy in both pounds and R-value—plan lifts, plank paths, and hatch reinforcement like any thick attic job.
Unfacing matters for retrofit science: you may be blowing air sealing first, then laying batts across a conditioned attic floor, or detailing a hybrid with rigid board at the roofline. Without kraft, you are not forced into factory-facing orientation; you still must follow IECC and IRC for thermal and ignition barriers, recessed lights, and access hatches. Split batts around truss webs, keep eave vents open where vented attics are required, and avoid second-guessing compression at mechanical platforms.
The product is manufactured to ASTM C665. Unfaced glass fiber insulation is classified noncombustible per ASTM E136 in manufacturer documentation, and unfaced PINK Next Gen is listed for ICC construction types I through V when used per OC literature. GREENGUARD certification with formaldehyde-free validation and a UL Environment EPD support typical submittals. Use the linked technical data sheet for handling weights, tested properties, and California Title 24 Article 3 language.
Attic takeoffs fail when teams confuse gross footprint with insulated plane area after kneewalls, dropped soffits, and mechanical decks interrupt the envelope; always model the insulated surface and then divide by the distributor-listed square feet per package for this SKU.
Logistics and safety are part of SEO-adjacent trust signals on thick high-R batts: package weights climb with R-49 thickness, so lift plans, attic flooring, and hatch reinforcement belong in the same conversation as thermal performance.
Submittal discipline: keep the distributor-listed dimensions (14.0 in. × 24.0 in. × 48.0 in.) and about 48.0 square feet per package attached to the same SKU on purchase orders, delivery tickets, and photos for QA. Authoritative tested language and code-oriented statements belong in the current manufacturer technical data sheet at https://www.idi-insulation.com/media/pdfresources/1000980_data_sheet.pdf.
Documents & certifications
Technical data sheet
Manufacturer-tested R-value, coverage, fire notes, and handling—use for submittals, RFIs, and field QA.
Download PDF (opens in new tab)Certifications & compliance
GREENGUARD (formaldehyde-free validated), UL Environment EPD, California Title 24 Article 3 insulating materials
Frequently asked questions
Is 48 sq ft per bag enough for my attic?
Is 48 sq ft per bag enough for my attic?
Divide your net insulated attic floor area by 48 square feet per package and add a real waste factor for truss heels, storage decks, and odd triangles. Do not confuse gross footprint with insulated plane area if kneewalls or dropped soffits change the geometry.
Can I compress BU92 under OSB storage platforms?
Can I compress BU92 under OSB storage platforms?
Compression reduces effective R-value for fiberglass. Either raise the platform, use an engineered detail that preserves thickness under the walkable area, or redesign with rigid foam or a different insulation system—do not hide over-compressed batts under plywood and call it R-49.
Does unfaced R-49 need a vapor retarder?
Does unfaced R-49 need a vapor retarder?
Vapor control is a climate and assembly decision under IECC and local amendments, not something the batt decides for you. Unfaced batts cooperate with separate poly, smart membranes, or kraft on another layer when your hygrothermal model calls for it.
Is this the same weight as R-38 batts?
Is this the same weight as R-38 batts?
R-49 at 14 in. thickness is materially heavier per bag than mid-R batts. Use the manufacturer data sheet for package weights, plan staged loading, and protect attic decking from point loads during delivery.