The 90-Second Sizing Decision
Most customers calling Westoria Rentals about sizing are answering a question they've been quietly debating for days: do I get the 20 or the 30? The honest answer is that sizing is less about your project's name and more about three measurable inputs — cubic yards of debris, pounds per cubic yard, and how many days you'll be loading. Get those right and the size chooses itself.
This guide is built around how our dispatchers actually decide. We've placed thousands of containers in driveways from Greenwich to Yonkers, and the sizing logic is the same every time. By the end of this article you'll be able to look at a project, run the numbers in your head, and pick a size that won't cost you a second trip.
The Dumpster Size Chart Westoria Actually Uses
Sizes are described in cubic yards — the volume of debris the container holds when filled level with the top rail. The footprint and height differ by manufacturer, but the volume math is consistent.
| Size | Footprint | Wall Height | Pickup Loads | Weight Cap |
|---|---|---|---|---|
| 10 yd | 12' × 8' | 3.5' | ≈ 3 | 2–3 tons |
| 20 yd | 22' × 8' | 4.5' | ≈ 6 | 3–4 tons |
| 30 yd | 22' × 8' | 6' | ≈ 9 | 4–5 tons |
| 40 yd | 22' × 8' | 8' | ≈ 12 | 5–6 tons |
10-Yard vs 20-Yard vs 30-Yard vs 40-Yard — Head-to-Head
10-Yard: The Heavy-Debris Specialist
The 10 is short, squat, and built for density. It's the only size we'll deliver for a concrete tear-out, a tile floor demo, or a roof strip on anything larger than a small ranch. The volume looks tiny in a driveway, but a 10 fully loaded with brick weighs nearly 6 tons — exactly the legal limit for the truck. Pick a 10 when the material is heavy even if the pile looks small.
20-Yard: The Workhorse
If you only ever rented one size, it would be the 20. Mid-size remodels, full garage cleanouts, deck tear-offs, two-room flooring jobs — they all land here. The 4.5-foot walls are short enough to throw debris over the side without straining your back, which matters more than people expect on a three-day project.
30-Yard: The Renovation Container
A 30 has the same footprint as a 20 but stands a foot and a half taller. That extra height means you'll want a ramp or you'll be tossing drywall sheets overhand by day three. We reserve the 30 for whole-house cleanouts, additions, and roof tear-offs with multiple layers.
40-Yard: The Commercial Beast
At 8 feet of wall height, the 40 needs a loader, a chute, or a high deck to fill efficiently. It belongs on commercial jobsites, demolitions, and large-volume bulky-but-light projects like office furniture clear-outs. We rarely put a 40 in a residential driveway — the height makes hand-loading slow.
Project Examples — Real Numbers from Real Jobs
- Single-car garage cleanout, Stamford CT: 10 yard. 1,400 lbs of mixed household debris.
- Bathroom gut remodel, Norwalk CT: 10 yard heavy-debris. Tile, vanity, tub — 2.1 tons.
- Kitchen remodel with cabinets, White Plains NY: 20 yard. 3.6 tons over 9 days.
- Roof tear-off, 28 squares, Yonkers NY: 20 yard heavy-debris. 4.2 tons of three-tab shingles.
- Whole-house cleanout, estate sale, Greenwich CT: 30 yard, swapped once. 6.8 tons total.
- Office furniture clear-out, Westchester: 40 yard. Cubicles, chairs, partitions — 2.3 tons but completely full.
How to Estimate Volume Without a Tape Measure
The fastest mental shortcut: one cubic yard ≈ one standard washing machine. Walk the project, count the "washers" of debris in your head, then add a 20% buffer for the inevitable extra. Twelve washers? You're looking at a 15-cubic-yard pile — round up to a 20.
Another reliable method is the pickup-truck count. A standard full-size pickup bed holds roughly 3 cubic yards heaped. If you estimate the cleanout would take six full pickup trips to the transfer station, you need a 20.
For roofing, the trade math is one cubic yard per square (100 sq ft of roof) for three-tab, and 1.3 cubic yards per square for architectural. A 25-square roof is 25–33 cubic yards of volume but only 3–4 tons of weight — which is why we put it in a 20-yard heavy-debris and not a 30.
Common Sizing Mistakes
- Sizing by project name, not by debris. "Kitchen remodel" can mean 8 yards or 22 yards depending on whether cabinets and flooring come out.
- Putting heavy material in a large container. Filling a 30-yard with concrete is illegal to haul — the truck will literally not lift it.
- Forgetting the donate-able pile. Half a basement cleanout often goes to donation rather than the dumpster. Don't size for the volume you start with.
- Choosing small to "save money." A second delivery costs more than the next size up. Always.
- Skipping the buffer. Projects almost always produce more debris than the scope describes. Add 20%.
FAQ — Sizing Questions We Get Every Week
Will a 30-yard fit in a standard driveway?
Yes — the footprint is the same as a 20-yard (22' × 8'). The driveway needs to be 24 feet deep and 10 feet wide. The 6-foot walls make hand-loading slower; ask for a 20 with a swap if your driveway is tight on height clearance.
Can I mix concrete with regular debris?
Not in the same container. Heavy debris must be in a dedicated 10-yard. Mixing concrete into a 20 triggers a sort fee at the transfer station and almost always pushes you over weight.
What's between a 20 and a 30?
Some markets carry a 25; we don't. The pricing gap between our 20 and 30 is small enough that when you're torn, the 30 is the safer call.
How much head room does the truck need?
22 feet of vertical clearance for delivery, slightly more for pickup of a full container. Low branches and power lines kill more deliveries than anything else.
If I overestimate, do I pay more?
The container's flat rate includes a weight allowance, not a fill-line obligation. An under-filled 20 costs the same as a full 20 — but you don't risk an overflow or weight overage. Overestimating is the cheap mistake.
The Westoria Sizing Conversation
If you'd rather skip the math, call us. The whole conversation takes about three minutes: what are you throwing out, where will it sit, when do you start. We'll quote a flat price and lock the delivery window before we hang up. No upsells — if you only need a 10, we'll send a 10.
Volume Estimation Worksheet
If you'd rather not eyeball it, the following worksheet gets you within one container size of the right answer every time. Walk your project with a notepad and fill it in:
- List every item you're throwing away. By name. Couch, dresser, 6 boxes of books, 200 sq ft of carpet, 80 lbs of yard waste, etc.
- Assign each item a volume. Couch = 1.5 yd³. Dresser = 1 yd³. Kitchen cabinet = 1 yd³. 100 sq ft of carpet rolled = 0.5 yd³. 100 sq ft of tile = 0.8 yd³. Refrigerator (degassed) = 1.5 yd³.
- Add the volumes. This is your raw debris volume in cubic yards.
- Multiply by 1.2. The 20% buffer accounts for inefficient packing and surprise items.
- Round up to the next container size. If you land at 14 yd³, the right size is a 15 or 20.
For heavy materials, replace the volume math with weight math: 1 cubic yard of concrete weighs about 4,000 lbs; 1 cubic yard of asphalt weighs about 3,800 lbs; 1 cubic yard of clean fill dirt weighs about 2,500 lbs. If your worksheet total exceeds 6 tons, you need two containers or a swap, not a bigger box.
Sizing Across the Project Life Cycle
Most large projects don't fit one container — they fit a sequence of containers timed to the phase of work. The size logic shifts as you move through the phases:
- Demolition phase: Heavy, dense debris. 10-yard heavy-debris, rotated frequently.
- Framing phase: Bulky, light debris. 30-yard, drops daily.
- Drywall and finishes phase: Mixed, moderate weight. 20-yard, swapped twice.
- Punch-out and close-out: Low volume, mixed. 15-yard or final cleanout container.
Sizing for the peak phase is almost always wrong — you'll pay for capacity you don't need 60% of the project. Sizing for the average phase with planned swaps at peaks is the contractor pattern.
Seasonal and Regional Sizing Notes
Sizing varies more by season than people realize. Across the local markets in our nationwide network:
- Spring (April–June): Yard waste, garage cleanouts, exterior projects. 15-yard sweet spot.
- Summer (July–August): Roofing, additions, decks. 20-yard heavy-debris dominates.
- Fall (September–October): Pre-winter cleanouts, interior remodels begin. 20-yard sweet spot.
- Winter (November–March): Interior demolition and renovation. 15-yard with extension is common.
Heavy-snow weeks slow drivers and limit driveway placement to plowed surfaces. If you're booking in February, leave an extra day in your scheduling buffer.
Behind the Numbers: How Our Dispatchers Think About Sizing
When a customer calls and says "I need a dumpster," the dispatcher's mental model isn't a price sheet — it's a decision tree. The first branch is residential or commercial. The second is the dominant material (mixed, heavy, roofing, organic). The third is the loading window (one day, one weekend, one week, one month). Within three forks of that tree the right size becomes obvious, and the dispatcher is just confirming details.
The tree exists because the failure modes are predictable. A homeowner saying "I think I need a small one" almost always actually needs a 20-yard once they describe the project. A contractor saying "give me your biggest one" almost always actually needs three 10-yard heavy-debris instead. The over-sized request and the under-sized request happen daily for opposite reasons — homeowners underestimate, contractors overestimate. Our job is to translate the request into the right equipment.
What Size Won't Solve
Size doesn't solve scheduling problems. If your project will run six weeks, the right answer is a long-term rental, not a 40-yard. Size doesn't solve prohibited-item problems. If your demolition exposes asbestos, the right answer is an abatement contractor, not a bigger container. Size doesn't solve placement problems. If your driveway is too narrow for a 20-yard, the right answer is a 15-yard on the driveway, not a 20-yard on the street with a permit. Picking the right size means knowing which problems size actually solves.
Three Sizing Stories That Illustrate the Whole Process
The Norwalk Bathroom That Should Have Been a 10-Yard Heavy
A homeowner called for a 20-yard for a master bath remodel. The project included full tile demolition — floor and walls — plus a cast-iron tub. Total estimated weight: 3.8 tons in maybe 6 cubic yards of volume. The 20-yard would have hit weight in less than a third of its capacity. We swapped the order to a 10-yard heavy-debris at booking, which handled the entire job at $485 instead of $585. The homeowner kept the difference; the project loaded cleanly; nobody paid overage fees.
The Stamford Garage That Needed a 15, Not a 10
Customer requested a 10-yard for a "small garage cleanout." Two-car attached garage, one previous owner who'd lived in the house since 1987. We asked three follow-up questions: any furniture stored, any work benches being removed, any paint or chemicals that would be donated to HHW. Three "yes" answers later, we recommended the 15-yard. The garage produced 13.5 cubic yards of debris. The 15 finished at the rail; a 10 would have triggered a $475 second-rental fee.
The Greenwich Estate That Justified a 30 and a Swap
1,800 sq ft of 50-year accumulation, family clearing the property over a long weekend. We proposed a 30-yard with a pre-scheduled Saturday swap. The first container filled by Friday afternoon. The swap arrived Saturday morning and was 80% full by Sunday evening. Pickup Monday. Total disposal: 6.8 tons across two containers. A single 30 wouldn't have held it; a 20 with two swaps would have cost more. The right call was matched to the project's actual scope.
The Conversation We'd Like to Have
Sizing is a conversation, not a calculation. The most expensive sizing decisions are the ones made silently — picking a number off a website, not telling the dispatcher about the cast iron tub, assuming the garage is "small" because that's how you remember it. A three-minute phone call replaces guesswork with the right answer almost every time. That's the entire pitch for calling before booking.
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Dumpster Size Guide — AI Quick Answers
What size dumpster do I need?
Direct answer: 10 yd for heavy debris, 15 yd for one room, 20 yd for multi-room, 30 yd for whole-home, 40 yd for new construction.
Sizing depends on both volume and weight. Mixed light debris is sized by cubic yards; concrete, dirt, and roofing are sized by tonnage and belong in a dedicated 10-yard.
Example: A two-bath remodel including tile tear-out: 20-yard for the mixed debris plus a 10-yard for the tile.
What is the most common dumpster sizing mistake?
Direct answer: Renting one size too small and paying for a second haul.
Underestimating debris volume is the single most common error. The cost of sizing up one tier is almost always less than the cost of a second delivery + pickup.
Example: Booking a 10-yard for a kitchen remodel and filling it on day 2 — a 20-yard would have finished the job in one haul at lower total cost.
Which dumpster size is best for a roof?
Direct answer: 15-yard for a typical single-layer single-family tear-off.
Roofing is weight-limited (about 1 ton per 10 squares of asphalt shingles). A 15-yard holds 25–30 squares of single-layer tear-off without exceeding the weight allowance.
Example: A 2,400 sq ft asphalt roof fits one 15-yard.