Topsoil Calculator for Lawns Sitting on Glacial Till
Enter your project dimensions
Before this topsoil calculator is any use, push a spade into the lawn and look at the side of the hole. Four inches of dark crumbly soil over more of the same is one situation. Two inches of thin gray material sitting on compacted till, with the spade stopping dead where the glacier left things, is another, and it changes both the depth you should enter and what you do before the soil arrives. The ground is visible from where you are standing, so start there.
What the side of a spade cut tells you about depth
Three readings, taken at the top of the slope, in the middle and at the low corner, will usually tell you the whole story of a yard.
If the existing layer is shallow and the material beneath it is dense, loam laid straight on top behaves like water in a dish. It saturates in the spring, stays wet into May and the grass roots never cross the join. The fix is not more topsoil; it is breaking the surface of the subgrade an inch or two deep first so the two layers knit, then adding the depth you planned.
If the low corner stays wet into summer while the rest dries, raising it with topsoil moves the puddle rather than removing it. Look at where the water is arriving from before ordering anything.
And if you hit ledge at six inches, plan the grade around it. Nothing on this page will change that, and spreading four inches of soil over a shelf of rock makes a lawn that browns first in a dry July.
Measuring a lawn with a patio in the middle of it
Rectangle covers a straight lawn. Circle takes a round bed or a turning area, entered on the full diameter. Multiple areas holds up to five, which is how a front lawn, a side strip and a back lawn get totaled in one go.
Measure the grass, not the property. Subtract a patio, a shed footprint or a driveway by measuring them separately and taking their square footage off the total before you enter it. On a big lawn that is often a full yard of soil.
Feet for the dimensions, inches for the depth, from 0.25 up to 24, which is the range that lets a half inch topdressing and a six inch bed sit on the same page. Select the material so the weight is right, leave the 5% box for compaction and spillage ticked if you want the margin, and press calculate for cubic yards, tons and cubic feet. The estimate can be emailed on to you.
Yards to plan with, tons to move: 2,200 lb between them
Topsoil is sold by the cubic yard, so the yard figure is the one to order against. The arithmetic is area in square feet times depth in inches divided by 12 for cubic feet, then divided by 27 for cubic yards. Tons follow from the weight this site publishes for screened topsoil, about 2,200 lb per cubic yard, or 1.10 tons.
Coverage at the depths that matter for lawn work:
| Depth | One cubic yard covers | Five cubic yards cover |
|---|---|---|
| 1/2 inch topdressing | 648 sq ft | 3,240 sq ft |
| 2 inches | 162 sq ft | 810 sq ft |
| 4 inches | 81 sq ft | 405 sq ft |
| 6 inches | 54 sq ft | 270 sq ft |
A soaked pile weighs considerably more per shovel than a dry one without covering an inch more ground, which is an argument for timing the delivery to the week you can actually spread it rather than the week you ordered it.
Depths for seed, for sod, for a topdressing pass
- Topdressing an established lawn: 1/4 to 1/2 inch, raked in so the grass tips stay visible.
- Preparing to overseed a thin lawn: 1/2 to 1 inch.
- A new lawn from seed or sod: 4 to 6 inches over a loosened subgrade.
- A flower bed being cut into existing lawn: 6 inches, mixed into the native soil rather than laid over it.
- Repairing a trench scar or a settled rut: the depth of the dip, measured with a board across it.
Beds that are being planted into want Garden Soil, the compost blend, rather than plain loam, and the soil calculator sizes that. If you are bringing a low area up by more than six inches, the bulk of that lift should be fill dirt with topsoil only in the top layer, and the dirt calculator handles it.
A 1,900-square-foot lawn and a half-inch pass over the back
Hypothetical jobs, worked through.
New lawn at 4 inches
1,900 square feet of prepared ground, seeded, with 4 inches of screened topsoil.
- 1,900 x 4 / 12 = 633.3 cu ft
- 633.3 / 27 = 23.46 cu yd
- 23.46 x 1.10 = 25.8 tons
With the 5% box ticked, 24.63 cubic yards and 27.1 tons. On a lawn that size, scarify the subgrade before any of it goes down and set the grade to fall away from the house.
Topdressing the back lawn
3,500 square feet at a half inch, after core aeration.
- 3,500 x 0.5 / 12 = 145.8 cu ft
- 145.8 / 27 = 5.40 cu yd
- 5.40 x 1.10 = 5.94 tons
Half an inch is genuinely thin. Drag it in with the back of a rake or a leveling bar so the existing grass comes through rather than getting buried.
The scar over a water line
Forty feet by three feet, settled about three inches below grade.
- 120 sq ft x 3 / 12 = 30 cu ft
- 30 / 27 = 1.11 cu yd, and 1.22 tons
Ordering a yard more than the lawn strictly needs
Lawns are not flat, and the difference between a calculation and a finished surface is always in the low spots. A spread that ends exactly level with the string line on paper will leave you short by a wheelbarrow or two once the dips have taken their share, and the last thing anyone wants is a seeded lawn waiting on a second delivery while the weather turns.
Round the yardage up, and use the balance in the corners, along the edge of a drive where the grade always wants building, and over any spot that settles in the first two weeks. Spread while the soil is friable rather than wet; a pile that has been rained on smears instead of raking.
When the number is right, set the quantity and the date on the product page. Delivery is arranged at checkout by ZIP code, and the truck needs clear access to a firm place to tip, ideally within wheelbarrow distance of the lawn and off the turf itself.
Common questions
What happens if the soil runs out with a strip of the lawn still bare?
You either wait on more material with prepared ground sitting open, which in this climate means a rainstorm re-grading it for you, or you thin the spread to make it reach, which shows up as a strip that dries out first every summer. Ordering a yard long avoids both.
How accurate is the yardage for a lawn that is not level?
The volume is exact for the numbers you enter, so the error lives in the depth. On an uneven lawn, take depth readings under a string line at three or four points and average them rather than using the depth at the high side.
The yardage is settled. Is screened topsoil what I want, or a blend?
Screened topsoil for lawns, grading and repairs. A compost blend for anything being planted into, which is a separate product and a separate tool. Both are ordered with the date set on the product page.
Where should ten yards of topsoil be tipped on a small lot?
On a firm level surface the truck can back onto, with a tarp under the pile, and as close to the work as access allows. Soil left on turf for a week kills what is under it, and soil on a slope moves before you do.
The estimate shows both yards and tons. Which number do I use?
Order by the yard, since that is how topsoil is sold and how it fills a space. The ton figure is what is on the truck and what you will move by wheelbarrow, which is useful for judging how many people and how many hours the spreading will take.
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Lawn math done? Soil's on us to deliver.
Screened topsoil by the cubic yard, free delivery across Connecticut.
