Cubic yards are the unit everyone in the disposal, landscaping, and concrete worlds uses, and almost nobody else thinks in. Whether you are ordering topsoil, pricing out a concrete pour, or trying to figure out how big a bin you need for a basement cleanout, knowing how to calculate cubic yards saves you money and guesswork.
The maths is simple once you see it. This guide walks through the basic formula, unit conversions, how to handle odd shapes and loose piles, why demolished material takes up more room than you would expect, and how to turn your answer into the right bin. If you would rather skip the arithmetic, our cubic yard calculator does it for you, including a weight estimate.
The basic formula
A cubic yard is a cube that measures 3 feet on every side. Since 3 times 3 times 3 is 27, one cubic yard equals 27 cubic feet.
So the formula is:
Length (feet) × Width (feet) × Height or depth (feet) ÷ 27 = cubic yards
Example: a pile of debris 9 feet long, 6 feet wide, and 3 feet high is 9 × 6 × 3 = 162 cubic feet. Divide by 27 and you get 6 cubic yards.
That is genuinely all there is to it for anything shaped roughly like a box. The rest of this guide is about handling the things that are not.
Converting inches and metres
Measurements rarely all arrive in feet.
Inches: divide by 12 to get feet. A 4-inch deep slab is 4 ÷ 12 = 0.33 feet. A 6-inch layer of soil is 0.5 feet.
Metres: if you measure in metres, calculate cubic metres first (length × width × depth in metres), then multiply by 1.308 to get cubic yards. For example, 3 metres × 2 metres × 1 metre = 6 cubic metres, and 6 × 1.308 = about 7.8 cubic yards.
Centimetres: divide by 100 to get metres first.
The most common mistake is mixing units, such as multiplying feet by inches. Convert everything to the same unit before you multiply.
Measuring rooms and structures
For renovation debris, you can often estimate volume from the size of what you are tearing out.
Flooring: multiply the floor area in square feet by the thickness in feet. A 200 square foot floor of tile and mortar about 1.5 inches thick (0.125 feet) is 200 × 0.125 = 25 cubic feet, or a little under 1 cubic yard in place.
Walls: the same idea works for plaster. Wall area times thickness gives you the volume in place. Plaster is so dense that weight matters more than volume, which our plaster walls guide explains.
Slabs and patios: length × width × thickness. A 12 by 10 foot patio, 4 inches thick, is 12 × 10 × 0.33 = 40 cubic feet, about 1.5 cubic yards in place.
Remember that these are in-place volumes. Once the material is broken up, it takes more space. More on that below.
Furniture and household contents are harder to measure this way, because they are all odd shapes and empty space. For a cleanout, it is often easier to think in pickup-truck loads: picture how many times you would fill a pickup bed with everything you are getting rid of, then multiply by about 2 to 3 cubic yards per load.
Measuring loose piles
Debris piles are rarely neat boxes. For a pile with sloped sides, measure the length and width at the base and the height at the highest point, calculate the box volume, then multiply by about one half. A heaped mound fills roughly half of the box you would draw around it.
For a long pile with a triangular cross-section, like a row of brush or soil, the same rule applies: multiply the box volume by one half.
For irregular piles, measure average dimensions rather than extremes. Pace out the typical length and width, and estimate a typical height rather than the peak.
Circles and odd shapes
Round areas, like the footprint of an above-ground pool or a circular garden bed, use the formula for a circle: π (about 3.14) × radius × radius × depth. A round bed 10 feet across has a radius of 5 feet, so 3.14 × 5 × 5 × 0.5 feet deep = about 39 cubic feet, or 1.5 cubic yards.
For complicated shapes, break them into simple pieces, like rectangles and triangles, calculate each one, and add them together. A triangle is half of the rectangle that contains it.
Swell: why broken material takes more room
Here is the part that catches people out. Solid material takes up more space once it is broken. A concrete slab has no air in it. The same slab, broken into chunks and thrown into a bin, is full of gaps between the pieces.
Rough rules of thumb:
- Broken concrete and masonry can take up around 40 to 50 percent more space than they did in place.
- Excavated soil typically swells by roughly 20 to 30 percent.
- Demolition debris from walls, decks, and structures can easily take up twice the space, or more, once torn apart, depending on how carefully it is broken down and loaded.
These are estimates, not precise figures, but the lesson is clear. If you measure something in place, size up. If you can measure the actual loose pile, do that instead.
From cubic yards to weight
Volume tells you whether something fits. Weight tells you whether a truck can lift it, and how much disposal costs. Here are rough weights per cubic yard for common loose materials:
| Material | Rough weight per cubic yard |
|---|---|
| Household junk and furniture | 0.06 to 0.11 tonnes |
| Renovation debris | 0.12 to 0.22 tonnes |
| Roofing shingles | 0.25 to 0.45 tonnes |
| Yard waste and brush | 0.04 to 0.10 tonnes |
| Soil or sod | 1.0 to 1.4 tonnes |
| Concrete, brick, asphalt | 1.1 to 1.4 tonnes |
Our standard rental includes 1 metric tonne of disposal, so a few cubic yards of soil or concrete reach that limit quickly, while a whole bin of household junk might not. Our guide to dumpster weight limits explains how weight affects your bin choice.
From cubic yards to a bin size
Our roll-off bins hold 10, 15, and 20 cubic yards. A 10-yard bin holds roughly three to four heaped pickup-truck loads. Pick the size just above your loose volume, and remember:
- If your estimate is close to a bin's capacity, go up a size. A slightly bigger bin costs less than a second delivery.
- Heavy materials like soil, concrete, and brick go in clean-fill bins through our dirt and concrete service, which are filled only partway so the truck can lift them.
- Yard projects with branches and brush suit our landscape debris bins.
Our bin size guide matches sizes to typical projects, and our guide to dumpster sizes in Canada explains the dimensions behind each size.
Worked examples
A basement cleanout pile: furniture and boxes stacked 12 feet long, 8 feet wide, and an average of 3 feet high. That is 12 × 8 × 3 = 288 cubic feet, or about 10.7 cubic yards. Size up to a 15-yard bin to be safe.
A patio slab: 14 by 12 feet, 4 inches thick. In place, 14 × 12 × 0.33 = 56 cubic feet, about 2 cubic yards. Broken up, that grows to roughly 3 cubic yards, and at well over a tonne per cubic yard it belongs in a clean-fill bin.
A garden bed dig: 25 feet by 5 feet, 8 inches deep. That is 25 × 5 × 0.67 = 84 cubic feet, about 3.1 cubic yards in place, closer to 4 once dug up. Soil is heavy, so this too is a clean-fill job.
Cubic yards for landscaping orders
The same maths works in reverse when you are ordering material rather than getting rid of it. Topsoil, mulch, and gravel are usually sold by the cubic yard, and the useful number to remember is this: one cubic yard spread 1 inch deep covers about 324 square feet.
From there, divide by the depth you want:
- At 2 inches deep, one cubic yard covers about 162 square feet.
- At 3 inches deep, a common depth for mulch, it covers about 108 square feet.
- At 4 inches deep, about 81 square feet.
- At 6 inches deep, about 54 square feet.
So a 400 square foot garden bed needing 3 inches of mulch takes about 400 ÷ 108, or a little under 4 cubic yards. Many people order slightly more than they calculate, since material settles and spreading is never perfectly even.
Wheelbarrows, pails, and other everyday measures
Sometimes the easiest way to measure a pile is with the container you are already using.
Wheelbarrows: a typical contractor wheelbarrow holds about 6 cubic feet when level-full, so four to five loads make a cubic yard. If you are digging out a garden bed or breaking up a patio, counting wheelbarrow loads as you go gives you a running total.
Pails: a standard 5-gallon pail, about 19 litres, holds roughly two-thirds of a cubic foot, so it takes about 40 pails to make a cubic yard. That is handy for small, dense jobs like plaster, tile, or mortar, where you are carrying debris out by the bucket anyway.
Garbage bags: a full large contractor bag holds a few cubic feet, so it takes several to make a cubic yard. Bags are a poor way to measure a big job, since they hide how much empty space is inside each one, but they work for small cleanouts.
For anything bigger, go back to length times width times height. It is still the most reliable method.
A quick reference
- 1 cubic yard = 27 cubic feet = about 0.765 cubic metres.
- 1 cubic metre = about 1.308 cubic yards = about 35.3 cubic feet.
- A full-size pickup bed holds roughly 2 cubic yards level, about 3 heaped.
- A 10-yard bin holds roughly three to four heaped pickup-truck loads; a 20-yard holds six to eight.
Common mistakes
- Mixing units, such as multiplying feet by inches.
- Measuring the peak of a pile instead of its average height.
- Forgetting swell when measuring something still in place.
- Ignoring weight with dense materials.
- Rounding down when you are between bin sizes.
Where we help
We deliver bins across southern and eastern Ontario, including Milton, Stouffville, Cambridge, and Belleville. Run your numbers through the cubic yard calculator, or call us with your measurements and we will help you choose.
