The main task of a drywall finisher, also known as a taper or plasterer, is to prepare unfinished interior drywall or other paperboards for painting or papering by taping, sealing and finishing joints in the drywall panels and repairing imperfections. First, the drywall finisher must mix the joint compound, either by hand or with a trowel, spatula or broadknife.
The finisher then spreads the joint compound into and alongside the joints using a wide, flat-tipped trowel. After spreading the compound, the finisher presses a paper tape into the joint and then spreads and smooths the joint compound over the tape with a trowel in order to make sure the joint blends in with the wall to create a flat, uniform surface.
Once the joint compound has dried, the finisher then sands any rough spots and fills in any screw indentations, holes or cracks in the walls or ceiling with sealing compound. In some cases, the drywall finisher may install metal molding on the corners instead of using tape and sealing compound. A drywall finisher may also use a roller or spray gun to apply primer and texturing compounds to walls and ceilings to prepare them for final finishing. Some drywall finishers may also be tasked with installing the drywall panels in addition to taping and finishing them.