Concrete Mix Ratio
Calculate amounts of cement, sand, gravel, and water.
Explanation
The concrete mix ratio is crucial for the strength of your structure. For foundations or a driveway, a mix of 350kg of cement per cubic meter is generally recommended. For less structural work like a walkway, 300kg/m³ may suffice. This calculator gives you the exact proportions of cement, sand, gravel, and water.
Examples
- To make 1 m³ of standard concrete (350kg/m³), you will need approximately 350 kg of cement, 630 kg of dry sand, 1230 kg of gravel, and 175 liters of water.
FAQ
What mix should I choose for a patio?
For a pedestrian patio, a mix of 300kg/m³ is standard. If it needs to support heavy loads, opt for 350kg/m³.
Can I use pre-mixed concrete aggregate?
Yes, pre-mixed aggregate (sand + gravel) simplifies the job. In this case, count on about 1800 to 1900 kg of mix for 1 m³ of concrete, to which you add the cement.
How much water should I add?
The general rule is to add about half the weight of the cement in water. Too much water weakens the concrete, too little makes it hard to work with.
Disclaimer
Always verify calculations with an architect or engineer before starting work.