Worked example — 12 ft × 10 ft bed, 3 in deep, 10% waste
Net volume is 12 × 10 × (3 ÷ 12) = 30 ft³ = 1.11 yd³. With 10% waste the bulk order is 1.3 yd³, or 17 of the 2 ft³ bags. That bag count is a comparison, not a recommendation to mix by hand.
Depth is the installed bed, not the bag
Measure the finished bed length and average width. Depth is what you want after it is raked, not the fluffy height in the bag. 2 in is a top-up. 3 in is a typical new bed. Bark and hardwood both settle — keep waste as its own input.
Bulk yards beat bags once you are past about a cubic yard. Construclytic still shows a 2 ft³ bag equivalent so you can compare, not so you mix 17 bags by hand as a default.
Mulch is not soil and not a truck load
Soil fill, gravel base and dump-truck loads are different densities. Do not convert a mulch yard into a 10-yard dump by eye. In Doha and the GCC, landscapers often sell by the cubic metre — switch the calculator to metric instead of converting a cubic-yard ticket.
Do it in order
- Enter finished bed length, average width and the installed depth you want after raking.
- Apply a settling and edge-waste allowance as its own percentage.
- Round to a bulk yard (or 2 ft³ bags on a tiny bed), then keep soil and haulage on other lines.
Planning boundary
This is a volume method. It does not pick a species, a dye, a weed-barrier spec or a live landscape price.
Sources
This guide is original worked arithmetic for the calculator linked above. It does not cite a laboratory test or a supplier price. The method, the internal check and the planning limit are on How we calculate.
Is 3 inches always enough?
It is a common new-bed start. A top-up is often 2 in. Enter the depth you will actually place.
Do I order the net yard?
No. Waste and supplier rounding stay visible. Shorting a bulk drop costs more than a leftover yard.
Is this a dump-truck load?
No. Open the dump-truck calculator once you have a haul volume.