Concrete Mix Proportions and Yield
Dry cement, sand, and aggregate lose about a third of their loose volume when mixed, and the yield factor turns a mix ratio into real material orders.
The equation
dry volume = 1.54 × wet volume
- 1.54 is the customary dry to wet volume factor
- Mix ratios like 1:2:4 are cement to sand to coarse aggregate by volume
- Cement bulk density is near 1,440 kilograms per cubic meter
Worked example
One cubic meter of 1:2:4 concrete needs 1.54 cubic meters of dry material, of which one seventh is cement: 0.22 cubic meters, about 317 kilograms, or 6.3 bags of 50 kilograms. The sand and aggregate follow at twice and four times the cement volume.
When to use it
Volume batching suits small works: structural concrete should be batched by weight to a designed strength. The 1.54 factor is a site convention, so let actual trial mixes overrule it where strength matters.
Related Calculators and Reference
- Excavation Cut and Fill Calculator: earthworks volumes from your levels.
- Construction Cost Risk Calculator: turn line item ranges into a confident budget.
- American Concrete Institute: authoritative guidance on concrete practice.