CMU Grout Volume (Partial and Full Grout)
The grout volume for a reinforced CMU wall.
Example
You enter
- Wall length (ft) 20
- Wall height (ft) 8
- Grouted-core spacing oc (in) 24
- Core cross-section (in², ~24 for 8 in) 24
- Bond-beam cross-section (in², 0 = none) 30
You get
- Grouted cores 11
- Vertical grout 14.67 ft^3
- Bond-beam grout 4.17 ft^3
- Total (ft³) 18.833
- Total (yd³) 0.698
No published worked example is on file for this calculation. It is checked against a hand-worked derivation of its method and an independent reference test.
Details, formula, and sources
ScopeGrouted cores at the rebar spacing (cores = floor(len x 12 / spacing) + 1) plus a continuous bond-beam course, in ft^3 and cubic yards. Core and bond cross-sections come from the unit data; the spacing comes from the structural drawings and the engineer of record governs the reinforcement - a material takeoff, not a structural design.
Formula or tablecores = ceil((wall_len_ft x 12 - 8) / core_spacing_in) + 1, capped at the wall's cells (centres 4 in from each end of a run of 16 in two-cell units, 8 in apart); vert_ft3 = cores x wall_ht_ft x (core_area_in2/144); bond_ft3 = wall_len_ft x (bond_area_in2/144); total_yd3 = (vert_ft3 + bond_ft3) / 27.
Source and editionFirst-principles core-count and grout-volume relations with TMS 602 / ACI 530.1 (Specification for Masonry Structures) and the NCMA TEK grout references (by name).
Free accessThe core-count and grout-volume relations are public masonry-takeoff geometry. TMS 602 / ACI 530.1 and the NCMA TEK references are named; the structural drawings supply the spacing and cross-sections.
What governsEstimate. AHJ and licensed professional govern.
API field nameswall_len_ft, wall_ht_ft, core_spacing_in, core_area_in2, bond_area_in2, cores, vert_ft3, bond_ft3, total_ft3, total_yd3
- Core count cores = ceil((wall length x 12 - 8) / spacing) + 1, both end cells grouted, never more than the cells (16 in two-cell units)first principles
- Grout volume vertical = cores x height x core area/144; bond beam = length x bond area/144 (one continuous top course)TMS 602 / ACI 530.1, NCMA TEK
- Cross-sections the grouted-core (~24 in^2 for an 8 in unit) and bond-beam (~30 in^2) areas come from the block manufacturer's dataunit manufacturer data