How to Build a Stone-Veneer Fireplace Surround

Cut the tip off the end of a grout bag, sizing your cut to the joint width. Fill the bag halfway with fresh grout mixed to the consistency of pudding. Twist the wide end of the bag shut, and squeeze grout toward the tip until all the air bubbles are gone and the grout reaches the opening. Starting with vertical "head" joints and moving on to horizontal "bed" joints, fill the joints with grout, always using an upward pulling motion as you work. (For the head joints, use a step stool if necessary to reach the highest stones.) Fill the joints until the grout is flush with or protrudes slightly from the face of the stones.