Step 2 of 2 · Materials

Split the mix into cement, sand and aggregate

Bring the specified ratio and dry-volume factor. The calculator shows how the finished volume turns into each bulk material. Your saved measurements and defaults are already in place; change anything that is different on this job.

Work item name

Measurements

Cement, sand and aggregate

These values stay read-only on the material page.

Change measurements or openings

Finished mix volume: 35.3 ft³

Using saved defaults

Standard sizes, ratios, wastage and rates are kept in one place instead of repeated on every item.

1:2:4 nominal mix50 kg cement bag5% wastage

The method, with an example

Formula

Dry volume = finished volume × dry factor. Each material receives its ratio share; cement converts from volume to bags.

Worked example

One cubic metre with a 1.54 factor and 1:2:4 split uses 1.54 m³ dry ingredients divided into seven total parts.

What this result assumes

• Ratio parts and dry-volume factor come from the applicable work specification.
• Cement bulk density and bag size are explicit inputs.

What it does not cover

• Moisture corrections, bulking of sand, admixtures and batching tolerances are not inferred.

Questions that come up on site

Why is dry volume larger than finished volume?

Loose ingredients contain voids and consolidate during mixing. The editable factor represents that planning allowance.

Can I use the default ratio for every job?

No. They are editable calculation examples and must be checked against the relevant specification.