Filling masonry walls with grout provides additional strength. It enables load-bearing masonry walls to be used for high-rise structures and in areas of severe earthquakes. TWO BASIC METHODS There are two ways to place grout: low-lift grouting and high-lift grouting. In low-lift grouting, usually no more than a 4-foot height of wall is grouted in 1 day and no cleanouts are used. Small amounts of grout are placed by hand with buckets. In high-lift grouting, cleanouts are used and up to a full story height is poured in 1 day using a grout pump. THE GROUT CREW A typical crew for a high-lift grouting operation using a grout pump has four workers. One handles the pump hose, directing the grout into position; another helps move the hose and prevents it from getting snagged. A third, working next to the hose, uses a puddling stick or vibrator to consolidate the grout. The fourth worker operates the pump, directs the ready mixed truck traffic, and maintains consistent, uniform flow of grout through the hose. THE GROUTING PROCEDURE Grout for high-lift grouting usually is supplied by ready mix trucks and pumped into place. For economical placement, pump a uniform height of grout not to exceed a 4-foot lift. Immediately after placement, consolidate the grout by vibration. PRECAUTIONS High-lift grouting can be quite economical. There are problems, however, that contractors should avoid: blowouts, vertical cell obstructions, and construction joints in the grout.