Specification

Submittal Sheet
Durock
®
Cement Board
1/4" Underlayment
1/4" Durock
®
cement board for floor and countertop applications
– 1/4" thickness helps eliminate trim when abutting carpet or wood flooring
– Easy to cut and fasten
– Water-durable and mold-resistant
– Will not rot, warp, delaminate or disintegrate
– Non-combustible
Description 1/4"
Durock cement board is an ideal substrate for floor and countertop ceramic tile installations. The 1/4" thick-
ness helps eliminate transition trim when abutting carpet or wood flooring and minimize level variations with other
finish materials. It can be applied directly over old substrate on countertops to save time. It features formed
smooth edges and square-cut ends.
Product Data
Sizes and Packaging Durock cement boards are 1/4" thick and 3' x 5'. 60 pieces per unit.
Standards Durock cement board exceeds ANSI standards for cementitious backer units (CBU). See ANSI A118.9 for test
methods and specifications for CBU and ANSI A108.11 for interior installation of CBU. Exceeds ASTM C1325
standards for non-asbestos fiber-mat reinforced cementitious backer units.
Availability Durock cement board is distributed throughout the United States. Contact a United States Gypsum Company sales
office or sales person for additional information.
Composition Durock cement board is formed in a continuous process of aggregated portland cement slurry with
and Materials
polymer-coated, glass-fiber mesh completely encompassing edges, back and front surfaces. The edges are
formed smooth. The ends are square cut.
Environmental In cold weather and during Durock cement panel and tile installation, temperatures within the building shall be
Conditions
maintained within the range of 40 to 100 °F. Adequate ventilation shall be provided to carry off excess moisture.
Delivery All materials should be delivered and stored in their original unopened package and stored in an enclosed
and Storage
materials shelter providing protection from damage and exposure to the elements. Even though the stability
and durability of
Durock cement board is unaffected by the elements, moisture and temperature variations may
have an effect on the bonding effectiveness of basecoats and adhesives. Store all
Durock cement board panels flat.
Interior Applications Wood framing shall approximate the moisture content it will reach in service by allowing the enclosed building to
stand as long as possible prior to the application of the cement board. Do not install board when the board is wet.
Panel Micro-Cracking Durock cement board is formulated to develop fine micro-cracking (also called multiple-cracking) in the panel.
The micro-cracking process helps to evenly relieve the stored strain energy in the product due to handling and
installation, external loads, and/or panel restrained movement. The presence of micro-cracks in the panel should
not be considered a product defect.