NCMA CMU-WR3

Full Name

NCMA CMU-WR3 – Standard Test Method for Assessing Water Uptake Potential of Concrete Masonry Units

Scope

The NCMA (National Concrete Masonry Association) CMU-WR3 standard test method provides a quantitative assessment of water absorption in concrete masonry units (CMUs). This laboratory test helps determine a CMU’s susceptibility to moisture migration, which can impact factors like durability, stain resistance, and thermal performance.

Test procedure:

  • CMU samples are oven-dried to remove any existing moisture.
  • The units are partially submerged in a shallow water bath for a specified period.
  • Following immersion, the CMUs are weighed to measure their weight gain due to water absorption.

Evaluation:

  • the NCMA CMU-WR3 test calculates the percentage of water absorbed by the CMU relative to its dry weight. This value provides a quantifiable measure of the unit’s water uptake potential.

Benefits of NCMA CMU-WR3 testing:

  • Quantitative data: provides a numerical value for water absorption, enabling objective comparisons between different CMUs.
  • Performance assessment: helps identify CMUs that may be susceptible to moisture-related problems.
  • Quality control: useful for ensuring CMUs meet project specifications and industry standards for water resistance.

Resources

Keywords

water absorption; concrete masonry unit; CMU; water uptake potential; moisture; quantitative; immersion; quality control