About the Product
These R12 fiberglass insulation rolls are an affordable, easy-to-install option for interior wall insulation and sound control. Sized for standard 16" on-center wall framing, the 15" width fits snugly between studs without excessive gaps or compression, while the 3.5" thickness suits typical 2×4 interior wall cavities. The roll format speeds up installation compared to batts — measure the cavity, unroll, cut to length, and place between framing members, trimming around electrical boxes or obstructions as needed. Fiberglass insulation slows heat transfer for year-round comfort, supports energy efficiency, and helps dampen sound between rooms, while its flexible structure conforms around wiring, plumbing, and minor framing irregularities. A practical, budget-friendly choice for homeowners, contractors, renovations, basements, and new construction on 16" o.c. framing.
Fiberglass Batts FAQ
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Rolls make sense for larger, continuous runs — attic floors, long wall sections, or floors over unheated spaces — where you're covering a lot of area and don't want to handle pre-cut pieces one at a time. Batts are usually faster for standard stud-bay walls where the cavity length already matches a pre-cut size; rolls give you more flexibility to cut custom lengths as you go.
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Yes. The 15" width is sized for standard 16" on-center wall framing, so it fits snugly into stud cavities the same way a batt would — you just unroll, measure, and cut to the height of the wall instead of using a pre-cut piece. It works equally well in walls, attic floors, and floor assemblies over unheated spaces like garages or crawlspaces.
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Rolls cut installation time on large, uninterrupted areas since you're not handling and fitting individual pieces — you unroll, cut to length, and place. They also let you customize the length exactly to your run instead of working around a fixed pre-cut size, which means less waste on non-standard cavity lengths.
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Measure the cavity, unroll the insulation, cut to length, and place it between framing members — trim around electrical boxes or obstructions as needed, and avoid compressing the material, which reduces its R-value.
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Fiberglass insulation is non-combustible and carries a low flame spread and smoke developed rating, making it a safe choice for standard residential and commercial framing. It won't provide the same fire-rated performance as rockwool, but it meets standard building code requirements for combustibility in typical wall and attic assemblies.
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Generally less, not more. Since you cut rolls to the exact length of each run, you're not stuck with the leftover offcuts that come from fitting a fixed-length batt into a non-standard cavity. The main waste consideration is storage — a partially used roll needs to be re-wrapped or kept clean until the next run.