Material Wastage Calculator

Turn your net design quantities into the amount you actually order after wastage — and into purchase units (cement bags, gravel m³, rebar lengths, CHB blocks, tiles, boxes, paint gallons). Use the Wastage list for a quick generic take-off, or pick a Material converter for concrete, reinforcing steel, masonry, tiles or paint. Countable items are always rounded up.

⭐ Free to use · Balance … EP

① Choose a mode

Wastage list: add one row per material, enter the net quantity and wastage %, and the app gives the quantity to order.

② Materials & wastage

② Material converter

Material

Net concrete volume (m³)

Mix class

Wastage %

Cement-per-m³, sand and gravel volumes are rule-of-thumb for the class — confirm against your concrete mix design.

Input by

Net total length (m)

Bar diameter Ø (mm)

Wastage %

Unit mass w = 0.006165·d² kg/m (d in mm). Commercial length = 6.0 m. Mass-input mode converts to length using the same unit mass.

Wall area (m²)

Block face

Wastage %

Indicative mortar factor: ≈ 0.5 bag cement & 0.044 m³ sand per m² of wall (Class B mortar, 10–12 mm joints) — confirm to your spec.

Area to tile (m²)

Tile size (m)

Wastage %

Pieces per box (optional)

Pieces are rounded up. If you enter pieces/box, the app also gives boxes (rounded up).

Area to paint (m²)

Coverage (m²/L)

Number of coats

Wastage %

Coverage is per coat; default ≈ 10 m²/L. Gallons assume a 4-L gallon, rounded up.

🧱 Order result

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Quantity to order

Summary

Worked solution

⚠️ Indicative estimate. Cement-per-m³, blocks-per-m², coverage and the default wastage allowances are TYPICAL/rule-of-thumb values — adjust to your mix design, block size, supplier coverage and site conditions. This is a quick take-off aid, not a substitute for a detailed bill of quantities.