15.25 in. width sized for 16 in. o.c. nominal 2×6 stud bays
Key features
93 in. length for eight-foot-ish wall modules and pre-cut stud workflows
Unfaced PINK Next Gen for designer-controlled vapor detailing
Technical specifications
| R-Value | 21.0 |
|---|---|
| Thickness | 5.5 in |
| Width | 15.25 in |
| Length | 93.0 in |
| Coverage | 68.94 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 | Cavity-fill fiberglass improves typical wall STC versus an empty cavity; assembly STC depends on studs, layers, and openings. |
| Density | Light-density flexible batt per ASTM C665 manufacturer listings; see TDS for product-specific values. |
| Thermal conductivity | See manufacturer TDS (ASTM C518) for tested thermal conductivity at labeled R-value. |
| Framing width | 15.25 in. width for 16 in. on-center stud spacing in nominal 2×6 walls. |
| 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 68.94 square feet per package (IDI-listed coverage). Primary use: nominal 2×6 exterior or partition walls on 16 in. on-center framing where the energy model calls for R-21-class cavity performance and the specifier wants unfaced fiberglass so vapor control can be executed with smart membranes, exterior foam, or separate interior layers.
BU107 mirrors the 15.25 in. width × 93 in. length geometry familiar from BF107 kraft batts, but removes factory kraft so you are not locked into integrated Class I vapor retarder facing from the insulation plant. That matters when assemblies use exterior continuous insulation, rain-screen reserve insulation, or climate-specific smart vapor retarders on the interior.
Execution still requires full labeled thickness, careful relief at pipes and outlets, and continuous alignment with the air barrier at rim, sill, and penetration clusters—compression is the fastest way to lose labeled R-value in fiberglass.
Manufactured to ASTM C665; unfaced glass fiber insulation is classified noncombustible per ASTM E136 in manufacturer documentation, with unfaced PINK Next Gen listed for ICC construction types I through V when installed per OC guidance. GREENGUARD certification with formaldehyde-free validation and a UL Environment EPD support typical submittals.
When estimators compare BU107 to BF107, the thermal story is similar but the hygrothermal story is not—document where vapor control lives in the same submittal package as the cavity insulation SKU.
Submittal discipline: keep the distributor-listed dimensions (5.5 in. × 15.25 in. × 93.0 in.) and about 68.94 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/1005515_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
BU107 versus BF107—which matches my vapor plan?
BU107 versus BF107—which matches my vapor plan?
BF107 adds kraft facing for integrated Class I vapor-retarder strategies when details allow. BU107 is unfaced at the same listed width and length per IDI—use it when vapor control is specified on another layer.
Why 15.25 in. width instead of 15 in.?
Why 15.25 in. width instead of 15 in.?
This SKU is distributor-listed at 15.25 in. width to fit nominal 2×6 walls on 16 in. on-center framing without over-compression—always verify dimensions on the master-pack label.
How do I estimate bags?
How do I estimate bags?
Divide net insulated wall area by about 68.94 square feet per package and add a waste factor for openings, corners, and odd cuts.
Is Next Gen the same density as legacy fiberglass?
Is Next Gen the same density as legacy fiberglass?
Use the manufacturer technical data sheet for product-specific ASTM C665 type language and tested thermal values—do not assume legacy datasheets apply to new SKUs.