How many bags of cement do I need for 1 cubic meter of concrete?

For a standard 1:2:4 mix (M15 grade), you need approximately 6.5 bags of 50kg cement per cubic meter of concrete. A 4×4 meter slab that is 10cm thick requires 1.6 m³ of concrete, needing about 10-11 cement bags plus sand and gravel.

What is the difference between M15 and M20 concrete?

M15 (1:2:4 mix) has a compressive strength of 15 MPa (2,175 psi) after 28 days, suitable for non-structural work like flooring. M20 (1:1.5:3 mix) reaches 20 MPa (2,900 psi), required for structural elements like beams, columns, and load-bearing walls.

How long does concrete take to cure?

Concrete reaches about 70% of its final strength after 7 days and 99% after 28 days. Keep the surface moist for the first 7 days by covering with plastic sheeting or spraying water. Full curing can take up to 90 days, but 28 days is the industry standard for strength testing.

Are the calculations on Concrete Calculator | Volume & Material Estimator Tool private?

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Concrete Calculator | Volume & Material

Concrete Calculator – Yardage EstimatorMetriova provides free online calculators for finance, business, health, and construction. Calculate loans, investments, fitness metrics, and project materials in seconds.Concrete Bag Yield: How Much Does Each Bag Cover?Pre-mixed concrete bags are sold by weight and yield specific volumes. An 80 lb bag yields 0.60 cubic feet. For a 4-inch thick slab, one 80 lb bag covers 1.8 sq ft. Formula: Bags Needed = Volume (cu ft) / Bag Yield. Always order 5-10% extra for spillage and uneven subgrades.

Bag Size

Yield (cu ft)

Coverage at 4" thick

40 lb bag

0.30 cu ft

0.9 sq ft

60 lb bag

0.45 cu ft

1.35 sq ft

80 lb bag

0.60 cu ft

1.8 sq ft