Calculator Inputs
Example Data Table
| Scenario | Dimensions | Factors | Volume (m³) | Mass (t) | Bags (25 kg) |
|---|---|---|---|---|---|
| Raised bed | 2.4 × 1.2 × 0.05 m (1 bed) | Compaction 5%, Waste 8% | 0.16 | 0.25 | 10 |
| Pathway strip | 8 × 0.8 × 0.04 m (1 area) | Compaction 7%, Waste 10% | 0.30 | 0.48 | 19 |
| Multiple beds | 1.8 × 0.9 × 0.06 m (4 beds) | Compaction 5%, Waste 12% | 0.49 | 0.78 | 31 |
Formula Used
- Base volume: V = L × W × D × N
- Compaction allowance: V₁ = V × (1 + C/100)
- Waste allowance: V₂ = V₁ × (1 + W%/100)
- Mass: kg = V₂ × density, tons = kg ÷ 1000
- Bags: bags = ceil(kg ÷ bag_size)
- Cost: depends on pricing method (per m³, per ton, or per bag).
How to Use This Calculator
- Measure the length, width, and planned sand thickness.
- Select the unit that matches your measurements.
- Enter how many identical beds or areas you will fill.
- Set compaction and waste percentages for realistic ordering.
- Adjust density if your sand is wet, dry, or compacted.
- Choose bag size if buying in bags, then pick a pricing method.
- Click Calculate to view results and download files.
Bedding sand roles in garden builds
Bedding sand is used to level pavers, support edging, and create a stable base under turf or raised beds. For paver bedding, many installers target 25–40 mm thickness after screeding. For small patio areas, even a 5 m² bed at 35 mm needs about 0.18 m³ before allowances.
Thickness choices and expected performance
Thickness is the biggest driver of volume. Doubling depth doubles sand demand. A 2.0 m × 1.0 m bed at 50 mm equals 0.10 m³; at 75 mm it becomes 0.15 m³. For pathways, 30–50 mm often balances drainage with firmness when compacted.
Density, moisture, and weight planning
Sand is commonly purchased by volume or by weight. Loose, dry sand can sit near 1400–1600 kg/m³, while damp or compacted material can approach 1700–2000 kg/m³. If your supplier sells by ton, changing density by 200 kg/m³ shifts a 0.50 m³ order by 0.10 t.
Allowances for compaction and handling losses
Compaction reduces voids, so ordering exactly the geometric volume can leave you short. Practical compaction allowances are often 3–10%, depending on moisture and how heavily you compact. Waste and spillage vary with access and wheelbarrow handling; 5–15% is common for home projects.
For deliveries, suppliers may quote in 0.25 m³ increments or minimum loads. If your final volume is 0.62 m³, rounding to 0.75 m³ can prevent delays and provides reserve for top-ups. This tool also converts to cubic yards (1 m³ ≈ 1.308 yd³) for mixed unit quotes. When buying by ton, verify whether the price uses metric or short tons and include hauling fees. Compare delivered versus ordered, and note any moisture claims.
Cost comparisons and bag-to-bulk decisions
Bagged sand is convenient for small jobs, but bulk delivery is usually cheaper per cubic meter. A 25 kg bag at 1600 kg/m³ represents about 0.016 m³. That means 60–65 bags roughly equal 1 m³, before allowances. Use the pricing method selector to compare per m³, per ton, or per bag quotes.
FAQs
1) What depth should I use for bedding sand under pavers?
For many garden pavers, a screeded bedding layer of about 25–40 mm is typical. Heavier traffic or uneven bases may need more base preparation rather than a thicker bedding layer.
2) Should I include a compaction allowance?
Yes. Compaction often reduces the placed thickness after tamping. Add 3–10% if you plan to compact, especially for long paths or patios where consistent levels matter.
3) How do I choose the right density value?
If you buy by weight, ask your supplier for bulk density at the expected moisture level. When unsure, 1600 kg/m³ is a reasonable starting point for many sands and small garden projects.
4) How many 25 kg bags equal one cubic meter?
At around 1600 kg/m³, one cubic meter weighs about 1600 kg. That is roughly 64 bags of 25 kg, before you add waste or compaction allowances.
5) Why does cost change when switching pricing methods?
Per m³ pricing depends only on volume, while per ton pricing depends on volume and density. Per bag pricing adds rounding, because you must buy whole bags even if you need a fraction.
6) Can I calculate different bed sizes in one run?
This version assumes all areas share the same dimensions. For mixed sizes, run the calculator for each size and add the volumes, or use the largest bed as a baseline and adjust with separate entries.