Problem Solving Forum
March 23 - March 27, 2020
How can you determine the moisture content of a concrete block (CMU) wall, and how can you judge when the moisture level is sufficiently low to paint?
yip L C of united chemicals co pte ltd on
March 25, 2020:
This is not much of a question in practical paint ...read more This is not much of a question in practical paint technology. Just feel the moisture content with your palm, and a cold surface indicates a moisture-laden concrete, which may be due to the state of cure or time of day or weather and rain. The old- fashioned test of covering an area with a plastic sheet and observing for condensation in a hour is a good one.. Paints nowadays are formulated with components that are moisture-tolerant unless the surface is literally, visibly wet.
ARTURO ESCOBEDO of TWILIGHT SA DE CV on
March 23, 2020:
I suggest a web search for instruments manuf ...read more I suggest a web search for instruments manufactured by moisture-detection specialists such as Delmhorst Instruments (USA), Imko Gmbh (GE), and Wagner Instruments (US) to name a few. These companies will recommend moisture detectors and/or meters through resistive, capacative, RF and/or sonar measuring principles. Some instruments are non-destructive tests, comparators, penetrating testers, etc. All-in-one testers are also available (penetrating+non-penetrating + % RH). ASTM F2170 provides criteria on concrete slabs but not on concrete blocks. Hopefully, you will receive a better reply than mine in this regard. I hope you can find your instrument shortly.