1-Pound Mass Loaded Vinyl (MLV)
1-Pound Mass Loaded Vinyl (MLV) is a dense, flexible sound barrier engineered to block noise through the principles of Mass Law and limp-mass behavior. Providing 1-Pound mass per square foot at ⅛" thickness, it layers with other acoustic materials to form a composite assembly that stops both airborne and structure-borne vibration between shared spaces.

- High-Mass Sound Blockage: 1 lb/ft² surface density significantly increases the mass of a partition, driving up resistance to sound waves crossing the assembly when seams and edges are properly sealed.
- Limp-Mass Barrier: Unlike rigid barriers, MLV's flexibility prevents resonant vibration that would otherwise re-radiate noise through the structure — improving barrier effectiveness across a broad frequency range.
- Broad Frequency Performance: Not absorptive like mineral wool, but its mass drives broad-band reduction of airborne noise for effective mid- and high-frequency transmission loss.
- Reliable & Safe Use: Durable, tear-resistant barrier with low odor. Compatible with common adhesives and sealants — confirm local fire/code requirements for the intended assembly.
Online orders up to 500 rolls. For anything larger, call (415) 864-4440 and we'll price the project with you.
Freight shipments include a $100 freight-and-handling charge.
1LB MLV Specifications
- Weight
- 1.0 lb per square foot
- Roll size
- 4' × 25' (100 sq ft)
- Thickness
- ⅛ in
- Fire rating
- ASTM E84 Class A
- Chemistry
- Lead-free, barium-free formulation
- Storage
- Keep dry, flat, or on-core; –40°F to 40°F
- Cutting
- Utility knife or scissors
- Install method
- Fasten with heavy-duty staples or screws with washers; assemble over insulated studs & behind sheathing/drywall layers
- Seam sealer
- Vinyl Seam Tape (not foil)
Vinyl Seam Tape
- Backing
- PVC vinyl
- Adhesive
- Pressure-sensitive acrylic
- Width
- 2"
- Roll Length
- 150 ft
- Thickness
- 6 mil
- Temperature Range
- -20°F to 180°F service
- Application
- Seals 1LB MLV seams and overlaps
- Compatibility
- MLV, MLV/EVA, painted gypsum, PVC
1LB MLV Project Calculator
Enter your surface square footage — we'll return the number of MLV rolls (each roll covers 100 sq ft) and the Vinyl Seam Tape rolls needed to seal every butt seam (1 seam-tape roll per 3 MLV rolls).
MLV is priced and installed by the 4' × 25' (100 sq ft) roll. Add a 10% waste allowance for cuts, overlaps, and perimeter sealing. Vinyl seam tape is required at every butt seam.
STC Gauge
Compare how the 1LB MLV performs across assembly tiers. Select an assembly below to see the resulting STC score.
Single ½" drywall each side, no insulation, no MLV.
- STC 30-39: Loud speech clearly audible next room.
- STC 40-49: Loud speech muffled — normal residential wall.
- STC 50-59: Loud speech barely audible; suitable for offices & multi-family.
- STC 60+: Approaches studio-grade isolation.
How 1LB MLV compares
| Model | Mass | Thickness | Primary Effect | Where It Shines | Notes |
|---|---|---|---|---|---|
| 1LB MLVthis | 1.0 lb/ft² | ~1/8 in | Blocks airborne noise | Retrofits, thin walls & ceilings | Seal seams & perimeter for best STC |
| 2LB MLV | 2.0 lb/ft² | ~1/4 in | Higher blocking | Demanding partitions | Heavier; fewer fasteners per seam |
| 5/8" Drywall + Green Glue | ~2.2 lb/ft² board + damping | ~5/8 in added | Mass + damping | Speech / music across wide band | Great with decoupling systems |
Applicable Assemblies
See where the 1LB MLV fits — from budget baseline to studio-grade isolation.
Best — Drywall + Studs + Insulation + Clips & Channels + MLV + Drywall + Green Glue + Drywall
Drywall · 2×4 framing · Rockwool insulation · Isolation Clips & Channels · 1 LB MLV · 5/8" drywall · Green Glue · 5/8" drywall.
Better — Drywall + Studs + Insulation + Clips & Channels + Drywall + Green Glue + Drywall
Drywall · 2×4 framing · Rockwool insulation · Isolation Clips & Channels · 5/8" drywall · Green Glue · 5/8" drywall.
Good — Drywall + Studs + Insulation + Clips & Channels + Drywall
Drywall · 2×4 framing · Rockwool insulation · Isolation Clips & Channels · single 5/8" drywall.



