Plastering Calculator
Calculate plaster bags and water needed for skim coating and bonding coats
Skim Coat Specification
Enter area and thickness
Total wall/ceiling area
Typically 2mm
From bag label - typically 10 m² per 25kg at 2mm
Mix losses and equipment - typically 10%
Check product - typically 11-12 litres per 25kg
Bonding Coat (Optional)
Results
Adjusted Area
110m²
Bags Required
📦12
Water Needed
138litres
💧 Water Note: Use clean water at room temperature. Mix thoroughly to correct consistency. Better to use slightly more water and have loose mix than too stiff.
⏱️ Drying Tip: Skim coats typically dry in 24-48 hours depending on temperature and humidity. Don't paint or sand until fully dry.
How to Use
- 1Measure total area to be plastered
- 2Set thickness: 2mm for skim, 10-15mm for bonding
- 3Enter product yield from bag label
- 4Account for 10% wastage (over-mixing, equipment loss)
- 5Enable bonding coat toggle if needed
- 6Calculate water volume for mixing
Example
100 m² skim coat project
Inputs:
Area: 100 m²\nThickness: 2mm (skim)\nProduct yield: 10 m² per bag\nWastage: 10%
Results:
Bags required: 11\nWater needed: 126.5 litres