What is the difference between face grouting and smearing mortar over the face of a joint?
Face grouting, described in the Brick Institute of America's Technical Notes 7F, is done using a mixture of cement and very fine aggregate instead of mortar. The face grout is more fluid than mortar and can be worked into cracks. It also has a higher ratio of cement to aggregate. The method of application also is different. Mortar usually is placed in joints using a trowel. In face grouting, a stiff brush is used to work the grout into any cracks in the joints. Mortar should never be applied in thin layers on the surface of joints because it can crack and fall out over time. Face grouting, on the other hand, has performed successfully.