Many contractors agree that grouting a wall a full story at a time is the most efficient method, and say they prefer it whenever conditions make it feasible. HIGH-LIFT GROUTING METHOD In high-lift grouting, the wall is laid up a full story and all reinforcing steel is installed before any grout is placed. Grout generally is delivered to the site in ready-mix trucks or produced onsite in silo mixers. Grout is transferred from the truck to a grout pump, which pumps it through a hose to the top of the wall. Grout is placed in lifts of 6 feet or less. It must be consolidated with a mechanical vibrator after each lift. The grouting crew usually consists of four or five workers. One handles the pump hose, directing the grout into position; another one or two help to move the hose and keep it from snagging. Another crew member operates a vibrator to consolidate the grout. INSTALLING REINFORCEMENT Methods used to install reinforcing steel vary. In some areas, codes require the steel to be in place before masonry units are laid. Given the choice, most contractors prefer a different method. One way is to install rebar positioners as the wall goes up, then lower full-length bars of vertical steel into the cores from the top of the wall. Some contractors prefer to install rebar in shorter lengths as the wall is built, lap-splicing and tying each length to the section below.