Topsoil Results
Calculation Breakdown
Formula Used
How to Use This Calculator
Choose a project preset or keep custom settings. Add every lawn, bed, or shaped section. Enter each section depth using your preferred measurement unit.
Select compaction, waste, and realistic soil density values. Enter bag sizes or bulk supplier pricing. Add delivery, labour, tax, and other project costs carefully.
Calculate and review volume, weight, ordering, and pricing. Compare bagged soil against bulk delivery totals. Confirm final quantities with your supplier before purchasing materials.
Recommended Topsoil Depth Examples
| Project | Typical depth | Suggested allowance | Planning note |
|---|---|---|---|
| Lawn topdressing | 0.25 to 0.5 inches | 5% waste | Keep grass tips visible after spreading. |
| New lawn | 4 to 6 inches | 10% compaction | Grade and lightly settle before seeding. |
| Flower bed | 6 to 12 inches | 10% waste | Blend amendments using local soil guidance. |
| Vegetable garden | 8 to 12 inches | 10% compaction | Use clean soil suited for edible crops. |
| Raised bed | 10 to 18 inches | 15% compaction | Settlement may continue after watering cycles. |
| Low-area levelling | Site dependent | 10% to 20% | Check drainage before adding deep soil layers. |
Frequently Asked Questions
How much topsoil do I need?
Measure every area and choose the required depth. The calculator combines all sections into one volume. Add allowances before placing your final supplier order carefully.
Should I include compaction?
Compaction allowance replaces volume lost during settling. New fills usually need more allowance than topdressing. Supplier guidance significantly improves estimates for local soil products.
Why add a waste allowance?
Waste covers spills, uneven ground, and measurement differences. Irregular sites generally need a larger percentage. Avoid excessive allowances for small, controlled garden bed projects.
Are cubic yards and cubic metres interchangeable?
They measure volume using different unit systems. One cubic yard equals about 0.7646 cubic metres. The calculator performs these conversions automatically for you instantly.
How are bag quantities calculated?
Adjusted volume divides by the selected bag volume. Partial bags always round upward for purchasing. Check printed bag volume labels instead of bag weight.
Can bag weight determine soil volume?
Bag weight alone cannot reliably determine soil volume. Moisture and composition greatly change topsoil density. Use bag volume whenever manufacturers provide that information clearly.
What density should I choose?
Choose a density matching the supplier's soil condition. Wet soil usually weighs more than screened soil. Use custom density when verified product data exists locally.
How does replacement mode work?
Replacement mode subtracts retained soil from entered excavation depth. Negative effective depths are treated as zero. This estimates only the soil volume being replaced onsite.
How many truckloads will I need?
Adjusted volume divides by the selected truck capacity. Partial truckloads round upward for scheduling purposes. Supplier limits may change actual delivery arrangements for projects.
Is bulk topsoil cheaper than bags?
Bulk orders often reduce cost for large projects. Delivery charges can change the final comparison. Review both totals before choosing your purchase method carefully.
Should I order exactly the calculated amount?
Calculated quantities remain estimates for planning purposes. Site levels and supplier measurements can differ. Confirm minimum orders and rounding rules before purchasing topsoil.