Grout shall be a plastic mix suitable for pumping without segregation of the constituents and shall be mixed thoroughly. Grout shall be placed by pumping or by an approved alternate method and shall be placed before any initial set occurs and not more than 11/2 hours after water has been added. Grout shall be consolidated by puddling or mechanical vibrating during placing and reconsolidated after excess moisture has been absorbed but before plasticity is lost. Grout shall not be pumped through aluminum pipes.
Maximum pour heights and the minimum dimensions of spaces provided for grout placement shall conform to Table R606.3.5.1. Grout shall be poured in lifts of 8-foot (2438 mm) maximum height. Where a total grout pour exceeds 8 feet (2438 mm) in height, the grout shall be placed in lifts not exceeding 64 inches (1626 mm) and special inspection during grouting shall be required. If the work is stopped for 1 hour or longer, the horizontal construction joints shall be formed by stopping all tiers at the same elevation and with the grout 1 inch (25 mm) below the top.
GROUT SPACE DIMENSIONS AND POUR HEIGHTS
| GROUT TYPE | GROUT POUR MAXIMUM HEIGHT (feet) | MINIMUM WIDTH OF GROUT SPACESa, b (inches) | MINIMUM GROUTb, c SPACE DIMENSIONS FOR GROUTING CELLS OF HOLLOW UNITS (inches × inches) |
| Fine | 1 | 0.75 | 1.5 × 2 |
| 5 | 2 | 2 × 3 | |
| 12 | 2.5 | 2.5 × 3 | |
| 24 | 3 | 3 × 3 | |
| Coarse | 1 | 1.5 | 1.5 × 3 |
| 5 | 2 | 2.5 × 3 | |
| 12 | 2.5 | 3 × 3 | |
| 24 | 3 | 3 × 4 |
For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm.
- For grouting between masonry wythes.
- Grout space dimension is the clear dimension between any masonry protrusion and shall be increased by the horizontal projection of the diameters of the horizontal bars within the cross section of the grout space.
- Area of vertical reinforcement shall not exceed 6 percent of the area of the grout space.
Requirements for grouted masonry construction shall be as follows:
- Masonry shall be built to preserve the unobstructed vertical continuity of the cells or spaces to be filled. In partially grouted construction, cross webs forming cells to be filled shall be full-bedded in mortar to prevent leakage of grout. Head and end joints shall be solidly filled with mortar for a distance in from the face of the wall or unit not less than the thickness of the longitudinal face shells.
- Vertical reinforcement shall be held in position at top and bottom and at intervals not exceeding 200 diameters of the reinforcement.
- Cells containing reinforcement shall be filled solidly with grout.
- The thickness of grout or mortar between masonry units and reinforcement shall be not less than 1/4 inch (6.4 mm), except that 1/4-inch (6.4 mm) bars shall be permitted to be laid in horizontal mortar joints not less than 1/2 inch (12.7 mm) thick, and steel wire reinforcement shall be permitted to be laid in horizontal mortar joints not less than twice the thickness of the wire diameter.