Problem Solving Forum
March 29 - April 2, 2021
What is an acceptable level of moisture in concrete walls before painting with an acrylic system, and how should the moisture level be measured?
Selected Answers
From
Zenith Czora of Durotech Industries, Inc. on
March 30, 2021:
Moisture levels can be required to be less than 2. ...read more
Moisture levels can be required to be less than 2.5 but not more than 5.5%. Bear in mind, depending on the type of moisture meter being used in measuring the moisture content, certain types of moisture meters only measure the condition of the surface layer. It is always recommended to check that there are no other sources of moisture. If there is an ongoing source of moisture within the masonry, this will drive the salt content of the cement toward the surface, causing efflorescence or salt-blooming that will lead to paint failure. Another method to qualitatively determine the moisture content is the plastic sheet method (ASTM D4263-83).