Grout & Tile Cleaning

The Coin Test for Finding Hollow Spots in Floor Tile

Hollow spots in floor tile are air pockets between the tile and the substrate caused by improper thin-set coverage or subfloor deflection. Detecting these voids early with the coin test prevents cracked grout and shattered ceramic. It is the most reliable low-tech diagnostic tool for homeowners and inspectors who need immediate results without expensive ultrasonic […]

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