Easily calculate cement, sand, and water needed for cement plaster. Supports metric & imperial units, price options, and custom mix ratios. Fast, reliable results.
Enter your measurements above to see the results.
Calculate the wet plaster volume by multiplying wall area by thickness (converted to m or ft). Apply a dry-volume factor (1.33) to account for bulking. Cement and sand are divided according to the chosen mix ratio. Sand is also displayed in tonnes/tons. Water is estimated at 20% of the total dry mix by weight. Total cost sums cement and sand costs based on the entered prices.
Inputs: Unit system: Metric; Wall area: 30 m²; Thickness: 12 mm; Ratio: 1:5; Bag size: 25 kg; Cement price/bag: £8; Sand price/tonne: £40; Currency: GBP. Calculated outputs: Plaster volume: 0.478 m³; Cement required: 114.72 kg; Cement bags: 4.6; Sand required: 573.62 kg; Sand in tonnes: 0.574; Water: 137.67 litres; Total cost: £196.33.
To estimate the materials for cement plaster, multiply your wall area by the desired thickness (converted to metres or inches as needed). The calculator applies a bulking factor to get the dry volume and splits it into cement and sand based on your chosen mix ratio.
Common ratios for cement plaster are 1:4, 1:5, or 1:6 (cement to sand). Use a stronger mix (like 1:4) for exteriors or wet areas, and lighter mixes for interiors. Custom ratios can be entered for special requirements.
This calculator works globally, supporting both metric (m, kg, litres) and imperial (ft, lb, gallons) units. Choose your preferred system and all results will be displayed accordingly, ensuring accuracy wherever you are.
Enter your local cement and sand prices, select your currency, and the calculator will estimate total material costs. This helps you budget accurately before starting your plastering project.
Always add water gradually and mix thoroughly for a consistent plaster. Adjust water based on workability and local conditions, and never exceed recommended water content to avoid weak plaster.
Yes, cement and plaster can be mixed to create a strong, durable wall finish. Cement plaster is commonly used for both interior and exterior walls, offering improved strength and weather resistance compared to gypsum-only plasters.
The standard cement plaster mix ratios are 1:4, 1:5, or 1:6 (cement:sand by volume). The right ratio depends on location and purpose—1:4 for exteriors or wet areas, 1:5 or 1:6 for interior walls.
To mix cement plaster, combine cement and sand in the desired ratio, mix thoroughly while dry, then gradually add water until the mixture reaches a workable consistency. Mix only as much as you can use before it sets.
Yes, a plaster mixer (mechanical or manual) can be used to mix cement plaster. Ensure the mixer is clean and add materials in the correct sequence for even mixing.
The exact amounts depend on your wall area, thickness, and chosen mix ratio. Use the calculator above to input your project details and instantly get the required quantities of cement and sand.
