How to Remove Thin-Set Mortar

By Robert Ferguson

Thin-set mortar is a cement-based material used to install tile and stone. Mixed with water, the adhesive is applied to a substrate using a notch trowel. During tile or stone demolition, the thin-set often remains attached to the substrate and is difficult to remove. Before installing new flooring material, it is recommended that any remaining thin-set be removed from the substrate. This provides a smooth and even surface to attach the new flooring. Although thin-set removal seems difficult, using the proper tools significantly reduces the amount of labor required.

List of Items Needed

  • Chipping hammer
  • Floor scraper
  • Oscillating tool
  • Rigid scraper blade accessory
  • Broom
  • Dustpan
  • Vacuum cleaner
  1. Remove any existing ceramic tile or stone using a chipping hammer. A chipping hammer is a power tool similar to a small jackhammer. When equipped with a chisel bit, the chipping hammer quickly dislodges all types of tile and stone from the substrate.

  2. Use a flat shovel and dustpan to remove the loose tile. Sweep the area thoroughly to remove any remaining debris and to expose areas where old thin-set still exists.

  3. Remove any remaining thin-set using a manual floor scraper equipped with a scraper blade or an oscillating tool equipped with a rigid scraper blade accessory. The floor scraper has a sharp blade attached that separates the thin-set from the substrate as it is plunged into the material. The electric oscillating tool equipped with the rigid scraper blade makes quick work of this task and requires significantly less labor compared to the manual floor scraper. The oscillating action of the tool combined with the rigid scraper blade accessory cuts through the thin-set as the tool is plunged into the material.

  4. Remove the thin-set debris from the area using a broom and dustpan. Use a vacuum to remove remaining dust and debris before installing new material.

Tips and Warnings

  • Keep a sharp eye on the power tool's cord to avoid cutting it during tool operation.
  • Wear protective gear such as gloves, dust masks, respirators and safety glasses when removing tile, stone and thin-set or operating power tools.
  • Use caution when operating power tools.

© Demand Media 2011