Plan render mixes for planters, fences, and features. Choose units, density, and bag sizes easily. See totals instantly, then export results to files securely.
These examples are illustrative. Always verify with your product specification.
| Area | Thickness | Coats | Waste | Density | Bag | Yield | Estimated Bags |
|---|---|---|---|---|---|---|---|
| 25 m² | 12 mm | 1 | 8% | 1600 kg/m³ | 25 kg | 1.30 | ~3–4 bags |
| 40 m² | 10 mm | 2 | 10% | 1700 kg/m³ | 25 kg | 1.35 | ~10–12 bags |
| 150 ft² | 0.5 in | 1 | 8% | 100 lb/ft³ | 55 lb | 1.30 | ~4–6 bags |
Garden masonry often includes porous blocks, old mortar, and algae. Clean to sound material, remove loose dust, then lightly pre-wet. Use a compatible bonding slurry or primer when surfaces are sealed or very smooth. Mask planting beds and protect drains to prevent cement contamination. Proper suction control improves adhesion and reduces rapid drying, especially in wind.
Thickness drives volume directly, so measure expected build carefully. Check plumb and flatness; deep hollows may need a leveling pass before the finish coat. A single 8–12 mm coat can suit planter walls, while two coats support durability on exposed boundaries. Keep each coat within the material limits to avoid sagging. Record coats separately when work is phased across days.
Waste factor covers rebound, over-troweling, edge losses, and small batch leftovers. Tight access behind shrubs or around irrigation hardware increases waste. When finish texture is heavy, allow more trimming and mixing losses. Include allowance for tools, buckets, and cleanup water that cannot be reused. Use realistic percentages to prevent mid-job shortages and visible color variation.
Yield factor converts placed wet volume into dry material needs because sand grading and entrained air vary. Manufacturer data is best, but 1.25–1.40 is common for site mixes. Density depends on aggregate, fibers, and polymers; higher density increases bag demand for the same thickness. Verify whether your product is a base coat, top coat, or one-coat system. Use product sheets for consistent procurement and compliance.
After mass is estimated, bags are rounded up to protect schedule and curing windows. Water per bag affects workability, shrinkage, and strength. Mix within recommended ranges, keep batches uniform, and track actual water usage for repeatability. Maintain the same mixing time and resting time across batches to stabilize texture. Store bags dry, and stage materials near work to reduce handling delays daily. Export results for ordering, logistics, and clear crew briefings.
Use the planned thickness per coat, not the total build. Measure a small test patch or follow the product guidance. If the surface is uneven, add a leveling coat separately and calculate it as an extra coat.
Start with 5–8% for open, simple walls. Use 10–15% for rough textures, many corners, or restricted access near plants and irrigation. Increase waste when mixing small batches or when weather causes rapid stiffening.
It converts placed wet volume into dry material requirement. Air content, sand grading, and additives change how much dry mass is needed. If your product lists coverage per bag, you can back-calculate an effective yield factor.
Yes. If coverage per bag at a stated thickness is available, you can estimate bags directly and treat density as informational. This calculator uses density for a flexible approach when coverage data is missing or mixed materials are used.
Procurement must account for partial bags, spillage, and touch-ups. Rounding up reduces the risk of stoppages and mismatched batches. Keep unopened surplus bags for future repairs or return if your supplier accepts them.
It affects total mix water shown and helps planning, but it does not change the dry mass calculation. Always mix within the recommended range. Excess water can weaken render and increase shrinkage cracking.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.