What the scale ticket actually measures
When the truck leaves your property and arrives at the transfer station, it rolls across a certified scale twice: once loaded, once empty. The difference between those two readings is the net weight of your debris. That number is printed on a scale ticket, and a copy of that ticket comes with your invoice. There is no estimate, no rounding in the operator's favour, and no guesswork, the weight is what the certified scale recorded.
The tonnage allowance in your quote is the weight included in the flat price. Windsordumpster states that allowance before you book, so you can compare it against what you expect to load. If the net weight on the ticket stays at or below the allowance, nothing extra is charged. If it goes over, the overage rate applies to every tonne above the line.
Tonnage allowances by bin size
Each container size carries a different included tonnage, and the gap between sizes is not just volume, it is weight capacity. Knowing the allowance for each size is the fastest way to spot whether a quote is genuinely cheaper or simply lighter on what it covers. These are the allowances we work with (example ranges, not quotes, rates vary by material and disposal destination):
- 6 yard bin, about 1 tonne included
- 10 yard bin, about 1.5 tonnes included
- 14 yard bin, about 1.5 tonnes included
- 15 yard bin, about 2 tonnes included
- 20 yard bin, about 2 tonnes included
- 30 yard bin, about 3 tonnes included
- 40 yard bin, about 3 tonnes included
Notice that the 10 and 14 share the same allowance, and the 15 and 20 share the same allowance. The extra volume in the larger bin is there for bulky, lightweight material, not for more heavy debris. If you are loading dense material, the volume step up does not buy you more weight room. Our bin size guide walks through both dimensions together.
Why heavy material needs a smaller bin
Soil weighs roughly a tonne per cubic yard. A 20 yard bin holds about 20 cubic yards of volume, which means a full load of soil would weigh around 20 tonnes, ten times the included allowance. The overage rate is $120 per tonne above the allowance (pricing depends on final scale weight and current disposal rates). Ten tonnes of overage on a 20 yard bin adds $1,200 to the invoice before you factor in the base rental.
This is why heavy material, soil, aggregate, brick, broken concrete, and similar inert debris, goes into a 6, 10, or 14 yard bin only, loaded on its own, and billed at the inert disposal rate rather than the mixed-waste rate. A smaller bin loaded to the fill line with clean fill weighs far less than a large bin with the same material spread across the bottom. Our page on heavy debris and clean fill explains how inert loads are priced differently.
How rain saturation adds unexpected weight
An open-top bin left outside during a heavy rain absorbs water into every porous material in the load. Drywall, insulation, cardboard, wood framing, and yard waste all hold water. A load of renovation debris that weighed 1.8 tonnes dry can easily reach 2.4 or 2.6 tonnes after two days of rain, pushing it past the 2-tonne allowance on a 15 or 20 yard bin and triggering overage charges on weight that was never part of the project.
The practical fix is straightforward: cover the bin with a tarp when rain is forecast, or schedule pickup before a wet stretch of weather. Most rental periods give you enough flexibility to time the collection. If you are on a longer project and cannot avoid rain exposure, factor extra weight into your estimate from the start. Our notes on rental periods and extensions explain how to adjust the schedule if the weather changes your timeline.
- Drywall absorbs water quickly and becomes significantly heavier within hours of rain
- Insulation batts can hold several times their dry weight in moisture
- Yard waste, grass clippings, leaves, branches, compacts and retains water heavily
- Cardboard and paper products dissolve into dense, wet mass at the bottom of the bin
- Wood framing and OSB sheathing swell and gain weight after prolonged exposure
Estimating your project weight before booking
Volume is what most people think about when sizing a bin, but weight is what determines the final bill. A useful starting point is to match the material type to a known density and work backwards from the bin's allowance. A 10 yard bin holds about three pickup truck loads of material and includes roughly 1.5 tonnes. If your load is light mixed waste, furniture, bags of clothing, general household items, that allowance is usually comfortable. If your load includes anything dense, the calculation changes fast.
For roofing tear-off, a 10 yard bin holds about 140 bundles of shingles and a 14 yard holds about 180. Shingles are heavy relative to their volume, so those bins are sized specifically for that material. Loading roofing waste into a 20 yard bin does not give you more weight room, it just costs more per tonne of allowance used. See the details on roofing tear-off bins for how those loads are typically structured.
How the overage rate is calculated
Overage is charged at $120 per tonne above the included allowance, based directly on the scale ticket (pricing depends on current disposal rates, rates vary). It is not a flat penalty and it is not rounded up to the nearest tonne. If your load comes in at 2.4 tonnes on a bin with a 2-tonne allowance, the overage charge is for 0.4 tonnes, which works out to $48 at that rate. The scale ticket shows the exact net weight, so the arithmetic is transparent.
The place most people lose money is not on a single heavy load, it is on a series of small overages across a longer project. Each bin comes back a few hundred kilograms over the allowance, and those charges accumulate across the invoice. The solution is to either increase the allowance at booking (some projects warrant it) or to pull the bin before it reaches the fill line and request a swap. Our full breakdown of weight limits and overage covers how to read the scale ticket line by line.
If you are comparing two quotes and one is noticeably cheaper, check the tonnage allowance first. A quote with a 1-tonne allowance on a 20 yard bin is not the same product as a quote with a 2-tonne allowance, even if the base price looks similar. The difference will show up on the invoice. Our post on what a bin rental quote should include lists every line to compare.
Prohibited items and disposal surcharges
Weight overages are not the only charge that can appear after pickup. If a prohibited item reaches the transfer station inside the bin, the receiving facility charges a separate disposal fee that passes directly to the customer. That fee is set by the facility, not by the rental operator, and it is typically much higher than a standard overage charge. Paint, solvents, fuels, oils, tires, batteries, propane tanks, hot water tanks, electronics, fluorescent tubes, and appliances still holding refrigerant are all refused at standard disposal rates.
- Paint and solvents, take to a household hazardous waste depot before loading the bin
- Tires and batteries, accepted at specific drop-off locations, not in a roll-off bin
- Propane tanks and fuel containers, must be empty and taken to a hazardous waste depot
- Hot water tanks, accepted as scrap metal only if drained and free of refrigerant
- Electronics and fluorescent tubes, require separate e-waste or lamp recycling drop-off
- Appliances holding refrigerant, must be degassed by a certified technician first
The full list of what the transfer station refuses is on our prohibited items page. Checking it before you load takes two minutes and can prevent a surcharge that dwarfs the original rental cost. If you are unsure whether something qualifies, our guide to avoiding extra fees covers the most common surprises.
Weight differences between residential and construction loads
A residential cleanout, furniture, boxes, clothing, small appliances, tends to run light relative to volume. A full 20 yard bin from a home cleanout or a garage and basement cleanout often comes in under the 2-tonne allowance because the material is mostly air and fabric. The bin fills visually long before it reaches the weight limit. For those projects, the risk is filling the bin past the top rail rather than going over on weight.
Construction and demolition debris is the opposite. Tile, concrete block, brick, and roofing material are all dense. A bin that looks half-full can already be at or near the allowance. For those loads, the fill line is not the constraint, the weight is. Our demolition debris page and the concrete and clean fill page both explain how to structure those loads to stay within the allowance or plan for overage from the start.