(415) 864-4440
Seam Tape

Reinforced Foil Seam Tape

Reinforced Foil Seam Tape combines the airtight bond of aluminum foil with an embedded scrim that resists tearing on long overhead spans, inside corners, and rough substrates. Its extra width and thickness bridge irregular gaps in Insulated Foil MLV and foil-backed acoustic underlay so the barrier layer performs as a continuous sheet. Peel-and-stick — cut, align, J-roll, done.

  • Scrim-Reinforced Strength: Embedded scrim resists tear-out on long overhead runs, over rough substrates, and at inside corners where lighter foil tape can split.
  • Wider, Thicker Coverage: 3" width and 6 mm thickness bridge irregular gaps in Insulated Foil MLV and foil-backed underlay for a fully sealed joint.
  • Airtight Foil Bond: Aluminum face bonds permanently to foil-faced barriers — the correct tape when the seam surface is foil, not vinyl.
  • Heat & Vapor Tolerant: Aluminum face resists heat and vapor drive — safe next to mechanical, HVAC, and radiant-floor assemblies.
  • Long-Term Adhesion: High-tack acrylic adhesive resists edge lift for the design life of the assembly.
$39.00
/ roll

Online orders up to 100 rolls. For anything larger, call (415) 864-4440 and we'll price the project with you.

Foil MLV-Compatible3" × 150 ft · 6 mmScrim-Reinforced
Product Specs

Reinforced Foil Seam Tape Specifications

Facing
Aluminum foil, scrim-reinforced
Adhesive
Pressure-sensitive acrylic
Width
3"
Roll Length
150 ft
Thickness
6 mm
Coverage
≈ 300 sqft of seam per roll
Application
Seals Insulated Foil MLV and foil-faced underlay seams on demanding spans
Service Temperature
-20°F to 250°F
VOC
Low — no curing required
Compatibility
Insulated Foil MLV, foil-faced acoustic underlay, foil vapor barriers
Companion Component

Foil MLV pipewrap

Composition
1 lb/ft² Foil-Faced MLV bonded to 1" quilted fiberglass
Nominal Thickness
1"
Standard Roll Size
48" W × 30' L
Areal Weight
1.22 lb/ft²
Temperature Range
-20°F to 350°F
Fire Rating
ASTM E84 Class A — FS 12.5 / SD 19.5
STC (barrier only)
29 (1"), 30 (2")
Seam sealer
Reinforced Foil Seam Tape (3" × 150 ft)
Use with
Tape every foil-faced overlap and termination airtight
Quantity Calculator

Reinforced Foil Seam Tape Project Calculator

Enter the total sqft of Insulated Foil MLV or foil-faced underlay to seam — we'll size the 3" × 150 ft roll count at 1 roll per 300 sqft. The 10% buffer only activates once 2 or more rolls are needed.

One roll of Reinforced Foil Seam Tape (3" × 150 ft) seals approximately 300 sqft of Insulated Foil MLV or foil-underlay seam. The +10% buffer only turns on when 2 or more rolls are needed for full coverage.

Estimated Materials
—Reinforced Foil Seam Tape rolls needed
Indicative only. Final quantities vary by framing spacing and access.
Sound Performance

STC Gauge

Compare how the Reinforced Foil Seam Tape performs across assembly tiers. Select an assembly below to see the resulting STC score.

Foil MLV rolls butted edge-to-edge without tape — small gaps and vibration at overlaps drop effective STC.

STC45
080
What the score means
  • 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.
Product Comparison

How Reinforced Foil Seam Tape compares

ModelPrimary UseFacingRoll SizeNotes
Reinforced Foil Seam TapethisFoil MLV seams on long/overhead runsScrim-reinforced foil3" × 150 ft · 6 mmExtra width & thickness for demanding spans
Foil Seam TapeInsulated Foil MLV & foil underlay seamsAluminum foil2" × 55 ydLightweight; ideal for shorter runs & corners
Vinyl Seam TapeStandard MLV & drywall seamsMatte PVC vinyl2" × 150 ftNot for foil-faced barriers
FAQ

Reinforced Foil Seam Tape — Common Questions

Choose Reinforced Foil Seam Tape for long overhead runs, inside corners, rough substrates, and floor underlay seams that see impact. Standard Foil Seam Tape is lighter and easier for shorter runs and hand-work.