Abstract: In its preferred form the present invention provides a tool for scarifying wallpaper, to create holes by which steam or water can get behind paper stuck to a wall and thereby assist in removing it. The tool includes a pair of sharp toothed wheels rotatably mounted at an angle to each other on a rolling or pivoting block, so that rolling or pivoting the block between two positions can alter the angle between the two wheels in relation to the wallpaper, to be appropriate for scarifying movement of the tool either backwards or forwards.

Abstract: A scarifying tool has a plurality of modules, each module consisting of a pair of cutter discs with bevelled teeth, rotatably mounted at an angle to the direction of travel to provide a sideways tearing action on the material to be dislodged as the discs are moved along the surface of the roof. Each module is mounted independently, to provide an independent suspension having several degrees of freedom. Adjustable depth control is provided by moving the discs relative to substrate contacting members to vary the depth of penetration of the cutters below the skids.