Guides
Longer answers to the questions that come up when you are about to order: how deep the mulch should be and how far a yard goes, how many bags of concrete it takes to make a yard and when to call the truck instead, and what a yard of stone actually weighs when it lands on your driveway.
- How much mulch do I need?Measuring beds of any shape, the right depth for each mulch type, a coverage chart per depth computed by the calculator, and bags versus bulk.
- How many bags of concrete make a cubic yard?The yields of 40 to 90 lb bags from the maker's data, a chart for common slabs and post holes, and how to think about bags versus ready-mix.
- How much does a cubic yard of gravel weigh?The density table with its sources, why the weight varies with rock type, fines and moisture, and how to convert yards to tons for an order.
Quick answers
- How much does a cubic yard of mulch cover? 162 sq ft at 2 in, 108 sq ft at 3 in, 81 sq ft at 4 in. The rule is 324 divided by the depth in inches.
- How many bags of mulch in a yard? 13.5 of the 2 cu ft bags or 9 of the 3 cu ft bags; 27 cubic feet divided by the bag size.
- How many bags of concrete in a yard? 45 of the 80 lb bags, at the maker's yield of 0.60 cubic feet each. Smaller bags, more of them.
- How many tons in a yard of gravel? Between about 1.22 and 1.39 tons for the stone in the calculators, depending on the rock and how much fines and moisture it carries. Ask the supplier for their own figure.
- How deep should mulch be? Two to three inches for fine shredded mulch, three to four for bark nuggets and wood chips, and none against trunks and stems.
- How thick should a patio slab be? Four inches over a compacted base for patios, walks and sheds; 5 to 6 in with reinforcement where trucks or RVs park.
- How much base under pavers? At least 4 in compacted for patios and walks, 6 in for driveways, more on clay or in freezing climates, plus 1 in of bedding sand.
Which calculator for which job
- A whole project (beds, path, patio, fence line): the project planner, which puts every area and material into one shopping list.
- Anything spread to a depth and bought by the yard or the bag: the mulch, topsoil, gravel and sand calculators, each with the depths and densities for its material.
- Poured concrete in slabs, footings, post holes, columns or stairs: the concrete calculator, in bags or ready-mix yards.
- A paver patio or walkway: the paver calculator, which counts the pavers and the base and sand under them together.
- A fence: the fence calculator for posts, rails, pickets, gates and the concrete per hole.
- Just the conversion from dimensions to yards, tons and bags: the cubic yard calculator.
How the estimates are computed, every formula, and where the densities and depths come from are on the methodology page. New guides and corrected figures are announced in the changelog.