Land Area Converter
Convert land area between Ropani-Anna-Paisa-Dam, Bigha-Kattha-Dhur, and standard units.
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About this calculator
Formula: Dry = 1.54 × wet; split by ratio shares · 2 inputs · step-by-step working
Quickly translate a concrete pour into cement bags plus sand and coarse aggregate volumes.
Formula
Dry = 1.54 × wet; split by ratio shares
How to Use
Enter the desired wet volume in m³ and the mix ratio (cement : sand : aggregate).
How the quantities are worked out
Enter the volume of finished (wet) concrete in cubic metres and a three-part mix ratio. The calculator multiplies the wet volume by 1.54 to get the dry volume of loose materials, then splits that dry volume by the ratio. For 1:1.5:3 the parts add up to 5.5, so cement takes 1/5.5 of the dry volume, sand 1.5/5.5 and aggregate 3/5.5.
Cement is converted to bags using a density of 1,440 kg/m³ and 50 kg per bag, so one bag is about 0.0347 m³. Sand and aggregate are shown in cubic metres; multiply by 35.31 if your supplier quotes in cubic feet. Water is not included, because the right amount depends on the cement, how wet the sand and aggregate are, and the workability needed on site. The figures have no waste allowance, so add 5 to 10% before ordering; 10% is safer for a first build or a hand-mixed pour.
Materials for 1 m³ of wet concrete (calculator output)
| Mix (cement : sand : aggregate) | Nominal grade | Cement (50 kg bags) | Sand (m³) | Aggregate (m³) |
|---|---|---|---|---|
| 1 : 1 : 2 | M25 | 11.1 | 0.39 | 0.77 |
| 1 : 1.5 : 3 | M20 | 8.1 | 0.42 | 0.84 |
| 1 : 2 : 4 | M15 | 6.3 | 0.44 | 0.88 |
| 1 : 3 : 6 | M10 | 4.4 | 0.46 | 0.92 |
The number after M is the characteristic compressive strength in N/mm² after 28 days of curing. Structural members such as columns, beams and slabs should use the grade on your structural drawings.
Worked examples
Work out the wet volume as length × width × thickness in metres, enter it with the mix, then add your waste allowance to the result.
| Job | Size | Wet volume | Mix | Cement | Sand | Aggregate |
|---|---|---|---|---|---|---|
| House floor slab | 20 ft × 15 ft × 4 in | 2.83 m³ | 1:1.5:3 | 22.8 bags | 1.19 m³ (about 42 cu ft) | 2.38 m³ (about 84 cu ft) |
| Pathway or driveway | 10 m × 2 m × 100 mm | 2 m³ | 1:2:4 | 12.7 bags | 0.88 m³ (about 31 cu ft) | 1.76 m³ (about 62 cu ft) |
| Square column | 0.3 m × 0.3 m × 3 m | 0.27 m³ | 1:1.5:3 | 2.2 bags | 0.11 m³ | 0.23 m³ |
With a 10% allowance the floor slab needs 22.8 × 1.1 = 25.1, so order 26 bags of cement and about 10% more sand and aggregate than shown.
Nepal site notes: cement, sand, aggregate and curing
- Cement: both OPC (Ordinary Portland Cement) and PPC (Portland Pozzolana Cement) are sold in 50 kg bags, and the calculator treats every bag the same way. PPC gains strength more slowly and gives off less heat while setting; OPC gains early strength faster. Which one a structural member needs is your engineer’s call.
- Sand: river sand has long been the default, but crushed (manufactured) sand is now common, especially in the Kathmandu Valley. It works in concrete but usually needs a little more water for the same workability, so keep an eye on the mix.
- Aggregate: 20 mm crushed stone chips are the usual coarse aggregate for structural concrete. Rounded river gravel is also used for non-structural work. The quantity is the same either way; tell the supplier which size and type you need.
- Mixing: hand mixing is manageable for small batches, but for slabs and columns a drum mixer gives a more even mix. Adding extra water to make concrete easier to place weakens it.
- Curing: keep new concrete continuously moist, commonly for at least 7 days with OPC and longer with PPC. In the dry months from Magh to Chaitra, cover slabs with wet hessian or plastic sheeting and water them regularly.
These are material estimates only. Foundations, columns, beams and slabs need a structural design that meets Nepal’s National Building Code, prepared and supervised by a licensed engineer.