Dumpster Size Calculator
Size a roll-off dumpster from the debris the job actually makes. Turns tear-out area, roofing squares or a room count into cubic yards, tons and a container size.
By CalcBuilt Editorial TeamUpdated September 9, 2026Formulas checked against manufacturer specs, see how we calculate.
Results
- Recommended container
- 20 cu yd roll-off
- Mixed construction debris. Holds 20 cu yd with 3 to 4 tons included in the flat rate
- Debris volume
- 12.04 cu yd
- 500 sq ft at 6 in deep, plus a 30% bulking allowance
- Estimated weight
- 2.92 tons
- 630 lb per cubic yard in place. Weight does not change when the material bulks up, only the volume does
- Containers to order
- 1 container
- One drop and one pick-up
- What fills it first
- Weight, not volume
- The box reaches 97% of its included tonnage at 60% full. Stop loading at the weight, not at the rails, or you pay overage
Dumpster Size formula
In-place volume (cu yd) = Area (sq ft) x Depth (ft) / 27
Loose volume (cu yd) = In-place volume x (1 + Bulking % / 100)
Weight (tons) = In-place volume x Density (lb per cu yd) / 2,000
Roofing weight (tons) = Roof area / 100 x Layers x Weight per square / 2,000Worked example
A 2,400 sq ft roof carries one layer of architectural shingles at 280 lb per square. That is 24 squares, and 24 x 280 = 6,720 lb, or 3.36 tons. At 1,000 lb per in-place cubic yard the shingles occupy 6.72 cubic yards, and a 30 percent bulking allowance puts 8.74 cubic yards in the box.
Volume alone would fit a 10 cu yd container, but the 10 only includes about 2 tons. The 20 cu yd box includes 3 tons, and 3.36 runs over. This job takes a 30 cu yd container, or a 20 with overage priced in. That is the whole point of checking both numbers: a tear-off looks small in the box and still buries the scale.
Quick reference
| Container | Typical dimensions | Weight included | What it holds |
|---|---|---|---|
| 10 cu yd | 12 x 8 x 3.5 ft | 2 to 3 tons | One bathroom gut, a small deck tear-off, about 10 squares of shingles |
| 20 cu yd | 22 x 8 x 4 ft | 3 to 4 tons | A kitchen gut, 500 sq ft of flooring, 20 squares of three-tab shingles |
| 30 cu yd | 22 x 8 x 6 ft | 4 to 5 tons | A whole floor remodel, siding on a small house, a full house cleanout |
| 40 cu yd | 22 x 8 x 8 ft | 5 to 6 tons | New construction scrap and other bulky, light debris |
| 10 cu yd heavy debris | 12 x 8 x 3.5 ft | 8 to 10 tons | Concrete, brick, asphalt or dirt, filled about three quarters |
What the invoice actually charges for
A roll-off quote is a flat rate that buys three things: the delivery, a set number of rental days, and a tonnage allowance at the disposal gate. Everything past that is a line item. Overage runs about $50 to $125 per ton in 2026 US markets, and extra days about $5 to $15 each. A dry run, where the truck arrives and cannot take the box, is usually charged as a full trip. The included tonnage is the number that catches people out. A 20 cu yd box with 3 tons included is full at 3 tons of tile or plaster long before the walls of the box are full.
Sort the load if the hauler offers a clean stream rate. Clean concrete, clean wood and metal often go for less per ton than mixed C&D. Connecticut DEEP and several other state programs list permitted processors that grind tear-off shingles into recycled asphalt pavement. That only works if the box holds shingles and nothing else. If the job includes a tear-off and a gut, order two boxes or run the tear-off first and swap.
Where the box lands and what cannot go in it
A roll-off truck needs about 60 ft of straight, level approach to slide a 20 cu yd box off the rails. Allow 10 to 12 ft of width and about 23 ft of overhead clearance to raise the hoist. Low branches, a carport, a gate arm and the service drop to the house all count. Put down two sheets of 3/4 in plywood under each rail and under the rear wheels. A full box is thousands of pounds on four narrow bearing points, and asphalt in summer heat gives way. On a street placement, check whether the city needs a right of way permit, which is common in dense towns and usually takes a few days.
Mixed containers are landfill or C&D processing loads, and several materials are banned from them. Appliances holding refrigerant need EPA Section 608 recovery before disposal, so a fridge, freezer, window AC or dehumidifier goes separately. Tires, wet paint, solvents, motor oil, batteries, fluorescent tubes and propane cylinders are all rejected. The hauler charges them back per item when they turn up at the gate. Asbestos containing material, which is common in pre-1980 floor tile, mastic and pipe insulation, needs licensed abatement and its own disposal path.
What this calculator leaves out
The result is a container size from volume and weight. It does not include the delivery and haul charge, disposal tonnage above the included allowance, extra rental days, or right of way permits. Fuel surcharges, environmental fees and per item fees for appliances and tires are also outside it. It does not cover abatement of asbestos or lead, the labor to break material down so the box loads efficiently, or the chute a second floor tear-out needs. Local disposal bans vary by state, so confirm the accepted list with the hauler before the box lands.
Mistakes that cost money
- Loading tile, plaster or wet carpet into a 20 yd box and going over 3 tons before the box looks half full.
- Putting concrete or dirt in a mixed construction box; it is billed at the mixed rate or refused at the transfer station.
- Skipping driveway protection. Loaded roll-off rails punch through asphalt; lay 3/4 in plywood under each rail and the wheels.
- Loading above the top rail. The driver cannot tarp it, so the excess comes back off before the truck moves.
- Tossing in a refrigerator, an AC unit, tires, paint or batteries; each one is charged back and some are refused at the gate.
- Assuming the rental is open ended. Seven to ten days is typical, and extra days run about $5 to $15 each.
Key facts
- Roll-off containers come in 10, 20, 30 and 40 cubic yards, and the 20 is the residential workhorse.
- EPA volume-to-weight factors put mixed C&D bulk at 484 lb per loose cubic yard and composition roofing at 731.
- NIST's survey of ICC-ES reports puts laminated architectural shingles near 280 lb per square; three-tab runs 200 to 250.
- Broken concrete and soil run about 3,400 lb per in-place cubic yard, so a heavy debris box hits 10 tons at roughly three quarters full.
- Overage past the included tonnage is typically $50 to $125 per ton in 2026 US markets.
Frequently asked questions
What size dumpster do I need for a roof tear-off?
A 20 square roof of architectural shingles is about 5,600 lb, or 2.8 tons, in roughly 7 cubic yards. The volume fits a 10 cu yd box, but its 2 ton allowance does not, so order a 20.
Can I put concrete or dirt in a regular dumpster?
No. Order a dedicated heavy debris box, usually a low 10 cu yd rated for 8 to 10 tons. Concrete runs about 3,400 lb per in-place cubic yard and will blow past a mixed container's allowance.
What happens if I go over the weight limit?
You are billed the overage, typically $50 to $125 per ton in 2026. If the load is over the truck's legal axle weight or heaped above the rails, the driver leaves it and you pay a dry run fee.
How much space does the truck need?
About 60 ft of straight approach, 10 to 12 ft of width and 23 ft of overhead clearance for the hoist. Watch for low branches, carports and the service drop to the house.
Sources and references
Next steps for this project
The usual order for a measurement & cost project. See all measurement & cost calculators.
Results are estimates based on standard formulas and typical product specifications. Confirm quantities with your supplier and local code before ordering.