A practical field guide to obtaining reliable moisture data before resin flooring installation
Premier Flooring Systems Ghana
| WHY THIS MATTERS
Concrete can appear dry while still carrying enough moisture to compromise a resin flooring system. Reliable decisions therefore depend on disciplined inspection, environmental measurements, moisture mapping, recognised test procedures and traceable records. |
A reliable moisture assessment is not a single reading. It is a controlled process.
Correct testing procedures are essential for obtaining dependable moisture data. Testing should follow recognised standards, manufacturer instructions and project specifications, with environmental conditions and test locations recorded before work begins.
1. Start with a Pre-Test Inspection
Before taking readings, inspect the slab for cracks, contamination, curing compounds, standing water, previous coatings, construction joints and signs of moisture ingress. Review the slab age, thickness, building history and whether a vapour barrier is present.
2. Record the Environmental Conditions
Measure and document ambient temperature, concrete surface temperature, relative humidity and dew point before testing. Stable environmental conditions improve the reliability and usefulness of the results.
3. Map the Floor for Elevated Moisture
Use a calibrated non-destructive concrete moisture meter to scan the floor and identify areas showing elevated moisture. Mark these locations for further investigation with recognised quantitative test methods.
4. Use ASTM F2170 In-Situ Relative Humidity Testing
Determine the required test locations, drill to the specified depth — typically 40% of slab thickness where the slab is drying from one side — clean the holes thoroughly, install sleeves and probes, allow sufficient equilibration time, and record RH and temperature. Compare the readings with the flooring manufacturer’s published limits.
5. Use ASTM F1869 Calcium Chloride Testing Where Applicable
Prepare the test area, place the calcium chloride dish, seal it beneath the test dome, leave it undisturbed for the specified duration, and calculate the Moisture Vapour Emission Rate (MVER) from the measured weight gain.
6. Treat the Plastic Sheet Test as Screening Only
A clear plastic sheet sealed to prepared concrete for approximately 16–24 hours can reveal condensation or surface darkening that may indicate excessive moisture. It should be treated only as a preliminary screening method, not as the sole basis for approving a substrate.
7. Record Results Properly
A professional moisture test report should capture project details, slab information, equipment used, calibration status, environmental conditions, test locations, readings, photographs and observations.
8. Interpret Results Against the Flooring System Requirements
Evaluate all readings against the flooring manufacturer’s requirements. If moisture exceeds acceptable limits, installation should be postponed until additional drying has occurred or an approved moisture mitigation system has been implemented.
9. Avoid Common Testing Errors
Incorrect probe depth, inadequate hole cleaning, insufficient equilibration time, poor calibration, testing immediately after washing the slab, ignoring environmental conditions and failing to document results can all undermine the reliability of the assessment.
10. Build Quality Assurance into the Process
Repeat testing where required, maintain traceable records and ensure all instruments remain within calibration. Independent verification may also be appropriate on critical projects.
Premier Flooring Systems Ghana Best Practice
| Combine visual inspection, environmental measurements, moisture mapping and ASTM-compliant testing. Never approve a substrate based solely on appearance or a single screening measurement. |
The Takeaway
Disciplined testing, accurate documentation and compliance with recognised standards provide the information needed to make informed installation decisions and reduce the risk of moisture-related flooring failures.
Coming Next
Moisture acceptance criteria: recommended relative humidity and MVER limits for different resin flooring systems, together with guidance on selecting suitable moisture mitigation solutions.
For engineers, consultants, facility managers and project teams, substrate moisture testing should be treated as a core quality-assurance step — not an optional pre-installation check.