Element being poured Slab / patio / driveway / footing pad Continuous footing (strip) Wall / stem wall Round column, pier or Sonotube Square or rectangular column / post hole Stairs (solid, cast on grade) Curb and gutter I already know the volume
How many identical elements e.g. 12 identical pier footings, or 1 slab.
Length Slab/footing/wall/curb length, or column side.
Width
Thickness / depth
Height Wall or column height.
Diameter (round column / Sonotube)
Number of steps
Step rise
Step run (tread depth)
Landing depth at the top of the stairs
Curb height above the gutter
Curb width
Gutter (flag) width
Gutter flag thickness
Known volume (ft3) Used only when the element is "I already know the volume".
Unit for length, height and landing depth Feet Inches Yards Metres Centimetres Millimetres
Unit for thickness, rise, run and flag thickness Feet Inches Yards Metres Centimetres Millimetres
Unit for width Feet Inches Yards Metres Centimetres Millimetres
Unit for the column / Sonotube diameter Feet Inches Yards Metres Centimetres Millimetres
Waste / over-order allowance (%) Covers subgrade irregularity, spillage and over-excavation. 5-10% is normal for a formed pour on a prepared base.
Bag size 40 lb bag (yields 0.3 cu ft) 50 lb bag (yields 0.375 cu ft) 60 lb bag (yields 0.45 cu ft) 80 lb bag (yields 0.6 cu ft) 90 lb bag (yields 0.675 cu ft) Yields are from the QUIKRETE Concrete Mix No. 1101 data sheet (0.0075 cu ft of concrete per pound of dry mix).
Bag yield override (ft3) Use the yield printed on your own bag if it differs (fast-setting, high-strength and crack-resistant mixes vary).
Hardened concrete density (lb/ft3) ASCE/SEI 7 Table C3.1-1a: 150 lb/ft3 reinforced stone concrete, 144 lb/ft3 plain. Lightweight mixes run 90-120. In metric those are 2400 and 2300 kg/m3.
Unit the density is given in Pounds per cubic foot Kilograms per cubic metre Normalweight concrete is 150 lb/ft3 or, equivalently, about 2400 kg/m3.
Ready-mix truck capacity (yd3)
On-site mix proportions (cement : sand : aggregate) Not needed (buying ready-mix or bagged concrete) 1 : 1.5 : 3 (M20, ~3000 psi) 1 : 2 : 3 (M20-M25 site mix) 1 : 2 : 4 (M15, ~2200 psi) 1 : 3 : 6 (M10, mass/lean) 1 : 1 : 2 (M25+, high strength) Only needed if you are batching from separate cement, sand and stone rather than buying concrete.
Dry (bulking) volume factor Dry loose ingredient volume needed per unit of placed wet concrete. 1.52-1.57 is standard practice.
Cement bag US sack, 94 lb (1 cu ft) Metric bag, 50 kg (0.0347 m3)
Water / cement ratio (by mass) Mass of mixing water per unit mass of cement. ACI 318-19 Table 19.3.2.1 caps w/cm at 0.50 for concrete exposed to freezing and thawing or to de-icing chemicals. Set 0 to skip the water figure.
Loose bulk density of the sand (lb/ft3) Used only to turn the batched sand volume into a weight. 100 lb/ft3 is the US EPA table figure for dry sand; use your supplier ticket when you have one.
Loose bulk density of the coarse aggregate (lb/ft3) US EPA table figure for crushed stone is 100 lb/ft3.
Delivered ready-mix price (USD/yd3)
Delivered ready-mix price (metric) (USD/m3) Use this instead of the price per cubic yard where concrete is sold by the cubic metre.
Price per bag (USD)
Delivery / trip charge (USD) Flat charge the supplier adds per delivery, on top of the concrete itself.
Supplier minimum load before a short-load fee (yd3) Orders under this size attract the short-load fee below. Leave at 0 if your supplier does not charge one.
Short-load fee (USD)
Placing and finishing labour (USD/ft2) Quoted rate for forming, placing and finishing, applied to the finished surface area. Ask your contractor; rates are local.