Concrete & Masonry Pocket Card — W/C Ratios, Rebar & Brick Sizes

One-page concrete card: ACI 211 water-cement ratios, US and metric rebar sizes and weights, and standard brick and block dimensions.


Updated August 20, 2026

The mix-design and take-off numbers a concrete or masonry crew reaches for, on one printable card: the ACI 211 water-cement ratio ladder against target strength for plain and air-entrained mixes, ASTM A615 US bar sizes with areas and weights, metric bar unit masses computed from exact geometry, and the specified dimensions and coverage rates of the common brick and block formats.

Every cell is generated from the constants behind the concrete mix, rebar weight, and brick & mortar calculators and the rebar size chart — psi equivalents come from the exact pascal definition of the psi, and metric kg/m from π/4·d²·7850, never retyped. The linked calculators turn these into batch weights, bar schedules, and unit counts.

W/C ratio vs strength (ACI 211)

28-day strengthNon-airAir-entrained
45 MPa (~6527 psi)0.35
40 MPa (~5802 psi)0.40
35 MPa (~5076 psi)0.440.35
30 MPa (~4351 psi)0.500.40
25 MPa (~3626 psi)0.570.46
20 MPa (~2901 psi)0.650.54
15 MPa (~2176 psi)0.750.63

Maximum w/c by mass for the target mean strength; — where ACI 211 publishes no air-entrained value. psi computed from MPa (1 psi = 6894.757 Pa).

US rebar sizes (ASTM A615)

BarSoft metricØ (in)Area (in²)lb/ft
#3No. 100.3750.110.376
#4No. 130.5000.200.668
#5No. 160.6250.311.043
#6No. 190.7500.441.502
#7No. 220.8750.602.044
#8No. 251.0000.792.670
#9No. 291.1281.003.400
#10No. 321.2701.274.303
#11No. 361.4101.565.313
#14No. 431.6932.257.650
#18No. 572.2574.0013.600

Nominal dimensions per A615 Table 1; mm diameters, mm² areas, and kg/m on the rebar size chart.

Metric rebar unit mass

Ø (mm)kg/m
80.395
100.617
120.888
161.578
202.466
253.853
326.313
409.865

Computed: kg/m = π/4 × d² × 7850 kg/m³ (≈ 0.006165·d²), the same function the rebar weight calculator uses.

Brick & block dimensions

UnitSpecified L × H × WJointCoverage
US modular brick7.625 × 2.25 × 3.625 in0.375 in6.86/ft²
US queen brick7.625 × 2.75 × 3 in0.375 in5.76/ft²
US king brick9.625 × 2.625 × 3 in0.375 in4.8/ft²
UK / metric standard brick215 × 65 × 102.5 mm10 mm60/m²
CMU 8 in block15.625 × 7.625 × 7.625 in0.375 in1.125/ft²
CMU 6 in block15.625 × 7.625 × 5.625 in0.375 in1.125/ft²
CMU 4 in block15.625 × 7.625 × 3.625 in0.375 in1.125/ft²

Specified (not nominal) dimensions with the standard joint; coverage is the published units-per-area rate.

Sources

  • ACI 211.1 water-cement ratio tables
  • ASTM A615/A615M Table 1; CRSI cross-check
  • Steel density 7850 kg/m³ (EN 1991-1-1) for computed metric masses
  • BIA / ASTM C652 brick formats and CMU nominal sizes

Try the Calculators