Quarter-round molding, or, as it is general called in carpenter’s vernacular, ‘a quarter-round,’ is a round length of wood, such as a dowel, which has been cut into quarters lengthwise, from the original round piece. A quarter-round will be exactly that size. It isn’t like dimensional lumber which might be slightly different than the marked size.
Most Common Quarter-Round
The ¾ inch quarter-round is the size most commonly used. It is set and nailed to the floor next to baseboards. The quarter-round will fit both flat to the floor and flat to the baseboard. In installing a piece of quarter-round, it is usually nailed with small brads.
In addition, it is sometimes advisable to use adhesive like Liquid Nails on the two flat sides of the quarter-round, so that there will be no pulling away from the wall. However, if a quarter-round is nailed in a sufficient number of spots along its length, there is no reason that a quarter-round won’t hold tight. Additionally, slight spaces along the edge of a quarter-round and the baseboard can be filled with caulking.