Johns Manville Self-Adhering Vapor Barrier, White, 5 Square Roll

This Johns Manville self-adhering vapor barrier is a white polyethylene-faced sheet supplied as a roll covering 5 squares. It adheres directly to the substrate to block vapor and moisture in roofing and wall assemblies, with one roll per sell unit.

Key Features:

• Self-adhering sheet: Adheres directly to the prepared substrate without mechanical fastening.
• Polyethylene construction: Made from polyethylene to resist moisture and vapor transmission.
• Five-square roll: Each roll covers 5 squares for efficient large-area installation.
• White finish: White sheet is easy to see during installation and inspection.
• Vapor protection: Functions as a vapor barrier within the building assembly.
• Continuous roll: Roll format reduces seams compared with narrow sheets.

Specifications Table:

Coverage & How Much You Need:

One roll covers 5 squares (500 sq ft). Divide the total barrier area by 500 sq ft per roll and add allowance for laps and cut waste when sizing the job.

Fit and Compatibility:

Use within Johns Manville roofing assemblies where a self-adhering vapor barrier is specified. Primers and termination or flashing accessories are sold separately.

Frequently Asked Questions (FAQ):

Q: What comes in one unit?
A: One self-adhering vapor barrier roll in white, covering 5 squares.

Q: How much does a roll cover?
A: Each roll covers 5 squares, about 500 square feet, before laps and waste.

Q: Is it self-adhering?
A: Yes, the sheet adheres directly to the prepared substrate.

Q: What material is it?
A: The barrier is made from polyethylene.

Q: What color is it?
A: White.

Q: Does it need primer?
A: Follow the manufacturer’s installation instructions regarding substrate priming and surface preparation.

Expert Verdict Reviewed by the SuperArbor Pro Desk

Self-adhering vapor barriers are most effective when applied to a clean, dry surface with laps rolled down fully to eliminate air pockets. The 5-square roll suits larger wall and roof-perimeter areas where narrow sheets would create too many seams. Coordinate the barrier placement with the roof or wall assembly design so it sits on the correct side of the insulation.

Install within the temperature range stated in the manufacturer’s instructions and use fall protection on elevated work surfaces.

Order the Johns Manville self-adhering white vapor barrier roll, 5 squares, to seal your roofing or wall assembly.