Unfortunately, there is no universal answer to this question. Different building types, varying project conditions (such as project schedule, reinforcement placement and congestion, trade coordination, weather, etc.), and preferences of the mason contractor or designer can all drive the use of one grouting procedure over the other. Despite their frequent use, the terms high-lift and low-lift grouting are not defined within current building codes or standards; rather these terms refer to the different processes of grout placement currently permitted. Prior to reviewing each of these procedures, however, users need to understand two additional terms when it comes to grout placement:
Grout Pour: the total height of masonry to be grouted prior to the construction of additional masonry (also referred to as pour height or drop height). A grout pour can consist of one or more grout lifts.

Grout Lift: the vertical height of grout placed at one time.

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