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A screening method is developed by predicting the strength of verylow-strength (< 9 MPa) concrete by the use of the rebound quotient and groove width from two low-energy, direction-independent nondestructive test methods (NDTs)--that is, a Type L rebound hammer and a scratching test--for brick and stone aggregate concrete. It is statistically demonstrated that low-strength concrete (LSC) exhibits a smaller standard deviation because of the low strength of the mortar phase, which ensures reliable LSC screening with any of the aforementioned methods. However, for higher-strength (> 9 MPa) concrete classes, due to the increase in standard deviation, the simultaneous use of the two methods is proposed with a conservative approach to estimate the in-place concrete strength during" rapid visual screening" of buildings. Normal distribution curves classify the concrete compressive strength considering NDT …