How moisture gets into concrete.
Measuring moisture content in concrete.
After 72 hours a humidity reading is taken under the plastic with a dew point hygrometer.
Thermo hygrometers sometimes called rh meters are a special kind of moisture testing device that can be used to monitor temperature and relative humidity conditions in a given area.
It is vitally important to test your concrete slab s moisture before installing flooring over it.
Some flooring system manufacturers have products that can handle 95 rh or mor 2.
Rh testing puts the test in the right spot to give accurate concrete moisture measurement.
Therefore measuring rh levels at 40 depth of the slab 20 depth if drying on two sides is more representative of the overall humidity conditions of the concrete.
Often more than one method is used to get an accurate reading of actual moisture content.
Astm international provides guidelines for rh testing in its standard f2170.
How concrete hardens and dries concrete is manufactured by mixing cement aggregates such as sand and gravel and water.
This is a relative scale.
These meters have been used for decades to measure the moisture content in different materials and substances.
Moisture meters include visual led indicators related to the percent reading on the scale for dry moderate and saturated or wet readings.
Astm f 2170 is the standard used to measure moisture deep in a concrete slab through the application of thermo hygrometers with in situ probes.
If the concrete is at 5 percent moisture content it will neither absorb nor desorb moisture if the air above it is 70 f 21 c and 75 percent rh.
When testing the moisture content in non wood materials such as concrete a relative scale of 0 to 100 is often used where 0 is bone dry and 100 is saturated.
There are three standard methods for measuring concrete moisture.
The test is performed by sealing an insulated box to the concrete and measur ing the relative humidity inside the box with a calibrated capacitance based humidi ty gauge.
Testing with either method will tell you how precisely how much moisture is present making it possible to choose a surface flooring that is appropriate.
A definitive test that measures the amount of moisture released from the concrete requires a calcium chloride kit or a relative humidity meter.
Acceptable moisture levels in concrete according to astm standard when testing via astm f2170 the rh level of a concrete slab needs to be at or below 75 unless the flooring system manufacturer provides alternate guidelines.
A concrete moisture meter is a type of moisture meter used by installers of flooring to measure the moisture levels of concrete.
According to astm f2170 when drying concrete slabs have lower moisture levels near the surface and higher levels towards the bottom of the slab.
