Specification

In the battle against interior moisture damage, the best
defense is a strong offense. When you block moisture vapor
from creeping behind finish materials or reaching moisture-
sensitive substrates, you help increase the useful life and
appearance of finish surfaces. To help win the battle, the
Fortifiber Building Systems
Group
®
offers Aquabar “B”
as inexpensive insurance to
reduce moisture-related
problems.
Aquabar “B” floor and tile
underlayment is an
extremely effective moisture
vapor retarder for use in a variety of interior
construction applications. Consisting of two layers of kraft paper laminated with
asphalt, Aquabar “B” is a non-reinforced 30/30/30 duplex type Grade “B” paper.
An Investment That Pays Dividends
Aquabar “B” is often considered to be cleaner and easier to work with than other
materials, such as roofing felt and poly film. Because it is an effective moisture
vapor retarder, Aquabar “B” reduces vapor migration to help protect wood floors,
tile substrates, and floor and wall cavities from the damaging effects of moisture.
Ideal for Wood Flooring and Tile
With a moisture vapor permeance of less than 1, Aquabar “B” is a superior vapor
retarder under wood flooring applications. Aquabar “B” helps slow moisture
vapor originating below the floor system, allowing the wood flooring to
acclimate gradually. By reducing the rate of moisture migration, Aquabar “B”
protects against moisture vapor related floor problems such as buckling, cupping
or cracking. As a semi-permeable material, Aquabar “B” is much less likely than
common poly film to trap moisture condensation between it and the sub-floor.
Aquabar “B” also acts as a “slip sheet” to minimize dust and reduce noise.
Aquabar “B” is also suitable in interior tile and stone applications as a moisture
retardant membrane (or cleavage membrane) on walls, countertops, or residential
showers for use behind cement backer units. It is also suitable for use as a
cleavage membrane in mortar bed applications over wood or concrete substrates.
Aquabar “B” reduces the potential for and extent of damage caused by moisture
vapor migration in tile installations.
Decades of Proven Performance
Aquabar “B” is a product manufactured by the Fortifiber Building Systems
Group. With more than a seventy year history of proven performance, technical
expertise and practical know-how, the company has become a trusted partner to
builders, architects and code officials.
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HIGH MOISTURE RESISTANCE
LOW VAPOR PERMEANCE
30/30/30 CONSTRUCTION
CLEAN & EASY INSTALLATION
“
An extremely effective
moisture vapor retarder
for use in a variety of
interior construction
applications.
”
TILE & FLOORING UNDERLAYMENT
®
Aquabar “B” helps slow
moisture vapor originating
below the wood floor system.