Plaster Calculator – Cement & Sand per m²

This tool applies the formula Plaster Volume = Area × Thickness; Cement = Volume × 1.33 ÷ 7 (1:6) directly to the measurements you enter, so the result is an exact quantity rather than a rough guess. Because plaster is priced and delivered per unit - cubic meters, square meters, bags or tonnes - a small measurement error multiplies across the entire order, which is why the calculation is worth doing properly. Worked example: A 100 m² wall at 12 mm needs 1.2 m³ plaster - about 10 bags of cement and 1.2 m³ sand at 1:6. One note from practice: Ceilings use a richer 1:4 mix because adhesion beats economy overhead. Enter the area, thickness and mix ratio, check the totals, then round up to the nearest whole bag, sheet or roll before you place the order.

1. 1

   Measure the space

   Record the area, thickness and mix ratio at the widest and longest points.

2. 2

   Enter the values

   Type the measurements into the calculator and select your units.

3. 3

   Apply the formula

   The tool computes Plaster Volume = Area × Thickness; Cement = Volume × 1.33 ÷ 7 (1:6) for your inputs instantly.

4. 4

   Add waste and order

   Review the total with a 5-10% margin and round up to whole units.

• Wrong unit count per area

• Mortar joints of uneven width

• Dry absorbing units