Topsoil Calculator for Screened Loam over Massachusetts Ground
Enter your project dimensions
Very few lawns in this state are rectangles. The usual shape is a side yard that narrows past the bulkhead, widens at the back corner, gets a bite taken out of it by a maple, and sits on stony glacial till that was never good growing soil to begin with. That is the lawn this topsoil calculator has to size, and the measurement is what decides whether the order is right, not the arithmetic.
Pacing out a lawn that narrows past the bulkhead
Take the long dimension along the whole run, then take the width in three or four places and average them. A strip 62 ft long that measures 19 ft at the house end and 27 ft at the back corner averages 23 ft, so 62 x 23 = 1,426 square feet. That single averaging step is worth more than any decimal place further down.
Three habits keep it honest. Pace or wheel the long dimension rather than throwing a tape across grass, because a tape sags and always reads short. Subtract anything that is not getting loam: a shed footprint, a patio, the root plate of a mature tree you are not burying. And measure the lawn you are treating, not the whole parcel, because the two are rarely the same once beds and hardstanding come out.
For a lawn that has a genuine dogleg, stop averaging and split it. Two rectangles entered as two areas beat one clever average every time.
Five areas, a circle for the tree ring, one total
Pick rectangle, circle, or multiple areas with up to five of them in one calculation. Lengths, widths and a circle diameter go in as feet. Depth goes in as inches and the field takes anything from 0.25 to 24, which is why a half-inch topdressing is a real entry rather than something to round up to one.
Choose the material so the right weight is applied, and leave the optional 5% for compaction and spillage ticked if you want the margin. The results come back as cubic yards, tons and cubic feet at once, and there is an email field if you would rather have them sent than written on the back of an envelope.
Half an inch to topdress, four to six inches to build
Depth is the input that moves the order most, and it is set entirely by what you are doing.
| Job | Depth |
|---|---|
| Topdressing established grass | 1/4 to 1/2 inch, raked through with the tips showing |
| Preparing for overseeding | 1/2 to 1 inch |
| New seeded or sodded lawn | 4 to 6 inches over a loosened subgrade |
| Finish grade over fill | 4 inches |
| New flower bed | 6 inches, blended into what is below |
Four to six inches is not a decorative figure. Over dense lower till, which most of eastern and central Massachusetts is working on, roots stop at the interface between imported loam and untouched hardpan. Rough up the existing surface an inch deep before spreading so the two layers knit, and keep the grade dropping away from the house over the first ten feet.
Deeper than six inches, stop buying loam. Bring the level up with fill and cap it, which is what the dirt calculator is for.
Cubic yards to order on, 2,200 lb a yard to move
The volume: square feet multiplied by depth in inches divided by 12 gives cubic feet, and cubic feet divided by 27 gives cubic yards. Loam is sold by the cubic yard, so that is the figure the order is placed on.
Tons come from the weight, and this site publishes screened topsoil at about 2,200 lb per cubic yard, which is 1.10 tons. The tonnage is the number that tells you what the day is going to be like: nineteen tons is a machine and a crew, four tons is a long afternoon with a wheelbarrow.
So the side yard above at 4 inches: 1,426 x 4 / 12 = 475.3 cu ft, then 475.3 / 27 = 17.6 cu yd, and 17.6 x 1.10 = 19.4 tons. With the 5% ticked, 18.5 cu yd and 20.3 tons.
Rain changes the weight of a pile and not the volume, so a wet week changes how the material handles, not what you order. It does argue for timing the drop for the week you are spreading, because soaked loam smears instead of raking.
A topdressing pass and a strip along a new walk
Two more hypothetical jobs, worked the same way.
Topdressing 2,400 sq ft of tired back lawn at a half inch. 2,400 x 0.5 / 12 = 100 cu ft, so 100 / 27 = 3.70 cu yd, and 3.70 x 1.10 = 4.07 tons. Rake it through so the grass tips stay visible; anything deeper smothers what you are trying to improve.
Strip along a new walk, 38 by 3 ft at 4 inches. 114 sq ft, so 114 x 4 / 12 = 38 cu ft, 38 / 27 = 1.41 cu yd, and 1.41 x 1.10 = 1.55 tons.
Order the round figure above whatever comes back. Low corners always take more than they measured, and a small shortfall on a seeded lawn shows as a thin patch for a whole season.
Where the pile lands is worth five minutes of thought. Loam on grass kills it within days, so put it on the driveway or on a tarp, and pick a spot that lets the wheelbarrow run downhill rather than up. Spring ground on dense till is soft, so the truck needs firm, clear access to the drop. Delivery is arranged at checkout by ZIP code.
Loam is the lawn and grading layer. Garden Soil is the compost blend for beds and planters, sized on the soil calculator. Put the two in the wrong places and you get an expensive lawn and a hungry vegetable bed.
Common questions
How close is this to what the lawn actually takes?
The arithmetic is exact; the measurement and the depth are the estimates. Averaged widths, a subgrade that is not as level as it looks and low corners all run one way, so real consumption sits a little above the calculated figure more often than below it.
I have a yardage. Which product page do I open?
Top Soil, which is the screened loam this page sizes. If what you calculated was the bulk under it, order Fill Dirt instead, and if it was a raised bed, order Garden Soil. Quantity and delivery date are set on the product page.
Where should twenty tons of loam be dropped on a house lot?
On hard standing, on a tarp, as close to the far end of the spreading run as the truck can safely get. Twenty tons is a substantial pile, so check the overhead clearance and the ground it is standing on, and keep it off any lawn you are planning to keep.
The screen shows tons and cubic yards. Which one do I order on?
Cubic yards, because loam sells by the yard. The tonnage is there so you know what is being moved and whether the job needs a machine. At 1.10 tons per yard the two figures sit close together, which is not true of the stone products.
Is the depth I enter the loose depth or the settled depth?
Enter the settled depth you want to end up with. Loam placed loose and then watered or walked in will drop noticeably, so spread a little proud of the target and let it firm rather than typing a bigger number into the box. A footprint pressing in about half an inch is about right.
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Screened topsoil by the cubic yard, free delivery across Massachusetts.
