Sand and aggregate in Hyderabad are sold by the lorry, quoted sometimes in tonnes and sometimes in cft, while mix designs and estimates use cubic metres. Converting between them, and knowing why loads disappoint, saves arguments and money.
Core Conversions
| From | To | Factor |
|---|---|---|
| Cubic metre | Cft | × 35.31 |
| Cft | Cubic metre | × 0.0283 |
| Tonne of dry sand | Cft | ≈ 22 – 24 |
| Tonne of 20 mm aggregate | Cft | ≈ 23 – 25 |
| Cubic metre of dry sand | Tonnes | ≈ 1.5 – 1.6 |
| Cubic metre of aggregate | Tonnes | ≈ 1.45 – 1.55 |
Densities vary with grading, source and moisture; M-sand is often a little denser than river sand.
Why Volume Loads Disappoint
Bulking. Damp sand traps films of water between grains, pushing them apart. At a few percent moisture, sand can occupy 20–30 percent more volume than when dry. A lorry of damp sand measured by volume holds noticeably less sand than the same volume dry.
Heaping and settling. A load heaped high at the yard settles during the drive; the volume at your gate is smaller than the volume loaded.
Measuring. A lorry's quoted capacity in cft assumes a level-full body. Measure length × width × height of the actual load.
Converting Estimates to Orders
Estimates for concrete and mortar give sand and aggregate in cubic metres. For example, 1 m³ of M20 needs about 0.42 m³ of sand and 0.84 m³ of aggregate:
| Item | m³ | Cft | Approx. tonnes |
|---|---|---|---|
| Sand per m³ of M20 | 0.42 | 14.8 | 0.65 |
| Aggregate per m³ of M20 | 0.84 | 29.7 | 1.26 |
Checking a Lorry Load
- Ask in advance whether the price is per tonne or per cft, and get a weighbridge slip if per tonne.
- For volume: measure the load's length, width and average height in feet; multiply for cft.
- Check moisture: very wet sand means less sand per cft, and more water in your mix.
- Check for silt: rub damp sand in your palm; heavy staining means excess fines.
The Short Version
Use 35.31 cft per m³ and about 22–25 cft per tonne. Buy by weight where you can, allow for bulking when you buy damp sand by volume, and measure what arrives rather than what was promised.
