Quick Answer: An 8×10 shed is 80 square feet and holds a push mower, bikes and tools; a 10×12 is 120 and takes a riding mower or a workbench; a 12×16 is 192 and becomes a workshop. Subtract a foot each way inside. Past 160 square feet a steel container costs less.
In This Guide
- Where We Stand
- Exterior Size Is Not Storage Size
- The Common Sizes, in One Table
- The 8×10: What It Actually Holds
- The 10×12: The Riding Mower Line
- The 12×16: Where a Shed Becomes a Workshop
- The Door Test Nobody Runs
- Why Everyone Says Go One Size Bigger
- What an Ontario Winter Does to Each Size
- The 160 Square Foot Crossover
- Container Sizes Beside Shed Sizes
- Who Should Buy Which
- Shed Size FAQs
Reading Time: 13 minutes
Where We Stand
This guide is written by a shipping container yard in Brantford, Ontario, which means we sell the steel box that competes with the largest sheds on this page and nothing that competes with the smallest. We say so up front. Most of the people who search for an 8×10 or a 10×12 should buy a shed, and the sections on those sizes are written to help them buy the right one. The container earns its section where the arithmetic actually turns in its favour, and not before. The sizing facts below come from the shed makers’ own guides, Keter, Duramax and the Ontario builders, read on September 15, 2026, and from thirty years of watching what people try to fit through a door.
Exterior Size Is Not Storage Size
The first thing to know about shed sizes is that the number on the box is the outside. A 10×12 shed is 10 feet by 12 feet at the outer face of the walls; inside, the studs, the sheathing and the trim take roughly a foot in each direction, so the floor you can actually stand things on is closer to 9 by 11. That is 99 square feet in a shed sold as 120. A container loses about two inches a side to its corrugation instead, which the container dimensions page tabulates. Resin sheds lose a little less because their walls are thinner; wood sheds with 2×4 framing lose the full foot; metal sheds lose the least on the walls and the most on the door, which is the subject of its own section below.
The second thing is height. Most kit sheds run a 6-foot wall with a peak somewhere between 7 and 8 feet, which means the usable wall for shelving stops at six feet and a tall person stoops at the eaves. A “high wall” option adds a foot for a reason. A shipping container, for comparison, is 7 feet 10 inches inside from floor to ceiling in the standard height and 8 feet 10 in the high cube, and its walls are vertical to the top, which is why sea can against shed, compared treats shelving as a point in the box’s favour.
The Common Sizes, in One Table
| Size (exterior) | Square feet | Roughly inside | What it comfortably holds | What it does not |
|---|---|---|---|---|
| 6×8 | 48 | 5×7 | Hand tools, a push mower, a bike or two | Patio furniture, anything with a deck |
| 8×8 | 64 | 7×7 | Push mower, bikes, garden tools, seasonal boxes | A second mower, a snowblower plus a mower |
| 8×10 | 80 | 7×9 | Push mower, snowblower, bikes, tools, camping gear | A riding mower; standing room once it is full |
| 10×10 | 100 | 9×9 | Everything above plus patio furniture for the winter | A riding mower with attachments |
| 10×12 | 120 | 9×11 | A riding mower, or a workbench with wall shelving, or a snowblower and a push mower and the bikes | A riding mower and a workbench together |
| 10×16 | 160 | 9×15 | Riding mower plus bench, or an ATV plus tools | Two machines and a bench |
| 12×16 | 192 | 11×15 | A workshop: bench, tools, a machine, room to turn around | Vehicle storage |
| 12×20 | 240 | 11×19 | Workshop plus a side-by-side or a small tractor | A car with the doors open |
Three sizes account for most of what Ontario buys, the 8×10, the 10×12 and the 12×16, and the rest of this guide takes them one at a time. The sixth row is the one to note in passing: 160 square feet is also the floor of a 20-foot shipping container, and the crossover section below is built on that coincidence.
The 8×10: What It Actually Holds
The 8×10 is the most-searched shed size in Canada for a plain reason: it is the largest shed that fits comfortably beside a suburban house without eating the yard, and it holds the list most households actually have. A push mower along one wall, a snowblower against the back, two or three bikes on hooks, the rakes and shovels on a rail, a shelf of seasonal boxes above, and the lawn chairs stacked in the corner. That is an 8×10 in October, and it works.
What it does not do is hold a riding mower. A typical lawn tractor is about six feet long with the deck and close to four feet wide, and once it is inside a 7-by-9 floor there is no room for the snowblower it was supposed to share space with, and the door has to be at least four feet wide to get it in at all. The makers’ own guides say the same thing: Keter and Duramax both describe the 8×10 as basic storage and stop short of the rider. Buy the 8×10 for the push-mower household, and buy it with the double door, because a 30-inch single door is the mistake that turns a good shed into a storage closet. The wood shed buyer’s guide covers what the walls are made of at this size, and the bike shed sizing page is the answer when the bikes are the whole point.
The 10×12: The Riding Mower Line
The 10×12 is the first size that takes a riding mower, and that single fact is why it is the second most-searched size and the one most Ontario shed sellers lead with. At 120 square feet outside and about 99 inside, the rider goes in along the long wall with room beside it for the push mower or the snowblower and the tools on the other wall. Or, if there is no rider, it is the first size that takes a real workbench: a six-foot bench across the back, shelving up both sides, and room to stand at it.
The honest limit is that it does one of those jobs, not both. A rider and a workbench in a 10×12 means the rider is parked in front of the bench and the bench is decoration. The makers’ guides describe the size as riding mower, snowblower and other sizable equipment, or a workshop with a bench, and the “or” is doing real work in that sentence. A buyer with both needs is a 12×16 buyer, and the section below says why the jump is worth it. For what to put the shed on, which matters more at this weight than at the 8×10, the gravel pad how-to applies to a shed exactly as it does to a container.
The 12×16: Where a Shed Becomes a Workshop
At 192 square feet outside and about 165 inside, the 12×16 is the size at which the word “shed” stops describing what people do in it. It holds a bench along one wall, a machine along the other, shelving to the ceiling, and a clear path down the middle to turn a wheelbarrow around. The makers’ guides list the same things: large equipment, multiple bicycles, bulk storage, a full workshop, a home office or a craft studio, which is to say a small building with a roof, sold as a kit.
That is also where the buying decision changes shape. A 12×16 needs a real base, usually a gravel pad or a slab, because its own weight and the weight of what goes in it will heave a shed set on patio stones. It needs a wider door, ideally a double 5-foot or a small overhead door, because the things that justify a 12×16 are the things that do not fit through a 4-foot opening. It is often built on site rather than assembled from panels, or delivered whole on a trailer that needs a clear run to the spot. And it is the first size where a buyer starts pricing per square foot rather than per shed, which is the arithmetic the crossover section is about. The she shed guide is the finished-interior version of this size, and container shed against a traditional shed runs the twenty-year cost of both.
The Door Test Nobody Runs
Before any size, measure the widest thing that has to go through the door. Most shed doors are 30 to 36 inches single, 48 to 60 inches double. A push mower needs about 24 inches; a two-stage snowblower 28 to 30; a riding mower 42 to 48 with the deck; an ATV 46 to 50; a side-by-side 60 to 64; a garden tractor with a bagger more than the double door on most kits. The shed’s floor can be the right size and the door can still be the reason the mower lives outside under a tarp. Metal kit sheds are the usual offenders, with sliding doors that open to two-thirds of their nominal width.
Height matters at the door too. A 6-foot door on a 6-foot wall is fine for a mower and wrong for a ladder carried upright, a canoe on its side or a person over six feet who uses the shed daily. The container comparison on this is simple: a standard shipping container’s cargo doors open to 7 feet 8 inches wide and 7 feet 5 inches high, the full width of the box, which is why the motorcycle and snowmobile storage guide never has to discuss whether the sled fits.
Why Everyone Says Go One Size Bigger
Every shed builder repeats it and it is true for a reason that has nothing to do with selling bigger sheds: the contents grow and the shed does not. A household that buys an 8×10 for the mower and the bikes adds a snowblower the next winter, patio furniture the winter after, and a second bike when a child grows. A 10×12 bought for the rider gets a bench squeezed in front of it. The cost step between sizes is smaller than the space step, because the roof, the door and the floor system are the expensive parts and a longer wall is cheap, so the 12×16 costs a fraction more than the 10×12 for 60 percent more floor.
The honest counter-argument is the yard. A shed sized for next decade’s contents can be the wrong shed for this year’s lot, and a 12×16 in a 30-foot-wide suburban backyard is a building, not a shed. Whether a given size can go on a given lot, and where, is your municipality’s call, so check with your local planning department before you order. Within that limit, buy the size that fits the yard and, if it is a tie, the larger one.
What an Ontario Winter Does to Each Size
Shed sizing guides are mostly written for climates without a February, and the Ontario version adds three things. Snow load first: a wider roof carries more snow, and the resin and thin-metal kits at 10×12 and up publish roof ratings for a reason; a 12×16 with an unrated roof under a wet March snowfall is the shed that appears on Facebook Marketplace as “free, some damage.” The Keter resin shed review reads those ratings line by line for the resin side, and the Lifetime resin shed review does the same for the heavier resin.
Frost heave second: the larger the shed, the more it matters that the base does not move, because a racked door on an 8×10 is annoying and a racked door on a 12×16 with a rider inside is a shed that will not open until April. A gravel pad with a drained perimeter, or a slab, is the answer from 10×12 up. And condensation third: a sealed shed of any size sweats in a thaw, and the bigger the roof the more water drips onto the mower; a ridge vent or gable vents are the fix on a shed, and passive against mechanical container ventilation is the same physics for a steel box. Where a shed and a container part ways in winter is the wall: a corten steel wall shrugs off the squirrel, the freeze-thaw and the snow load that finish a wood or resin panel, which is the argument the squirrel-damage photographs on the shed comparison make without words.
The 160 Square Foot Crossover
Here is the arithmetic that decides the top of the shed market, and it is the section this yard is qualified to write. A 20-foot shipping container is 8 feet wide and 20 feet long outside, 160 square feet, which is the 10×16 row of the table and sits between the 10×12 and the 12×16. Inside it is 7 feet 8 inches by 19 feet 4 inches, about 148 square feet, on a marine plywood floor over steel cross-members, with a steel roof rated for six loaded containers stacked on top of it, and doors the full width of the end. It arrives finished, on a tilt-deck, and is set on blocks or a gravel pad in an afternoon with no assembly.
| 12×16 kit shed | 20 ft used container | |
|---|---|---|
| Floor, outside | 192 sq ft | 160 sq ft |
| Floor, usable | About 165 sq ft | About 148 sq ft |
| Height inside | 6 to 8 ft, sloping | 7 ft 10 in, flat; 8 ft 10 in high cube |
| Door | Double 4 to 5 ft, or overhead as an option | 7 ft 8 in wide, 7 ft 5 in high, standard |
| Walls and roof | Wood, resin or thin steel panels; roof rated per model | Corrugated corten steel, welded; rated for ocean stacking |
| Base | Gravel pad or slab, prepared by you | Blocks or gravel pad; no slab needed |
| Assembly | A weekend for two, or a delivered build | None |
| Security | Hasp and padlock on a panel door | Four locking bars and a lock box welded over the hasp |
| Looks in a backyard | A shed; the better kits look like a small building | A steel box unless painted or screened |
| Twenty years on | Depends on the base, the roof and the maintenance | Still a container, with resale value |
Read the last two rows against each other, because they decide the purchase. A 12×16 kit in a fenced suburban yard, where the neighbours can see it and the contents are patio furniture and a mower, is the right building and the container is the wrong one; it is a steel box and it looks like one, whatever the paint. A 10×16 or 12×16 on a farm lane, a rural lot, a job site, a cottage road or behind a shop, where the contents are tools with resale value and the priorities are that it locks, it does not heave, and it is there this week, is a container job, and the per-square-foot line tips that way from about 160 square feet on, once the kit’s base, delivery, assembly and the first roof repair are counted. The container-as-shed page is what the steel answer looks like in practice, and the container grades decoder explains why a used wind-and-watertight unit is the grade a shed buyer wants.
Christian LeBlanc, Van Blanc: “The shed calls sort themselves by one question: what’s the biggest thing going in. If it’s a push mower and the bikes, I tell them to buy the 8×10 and put the money into the base. If it’s a rider or a snowmobile, or they say the word tools, I tell them a used twenty-footer costs about what a good 12×16 costs by the time the kit is standing, and it’ll still be standing when the kit isn’t.”
Container Sizes Beside Shed Sizes
For the buyer whose list has crossed the line, the container sizes map onto shed sizes more neatly than most people expect. A 10-foot container is 8 by 10 outside, the same footprint as the most-searched shed, about 70 square feet inside, and is the answer for a small lot that needs a steel box rather than a wood one; it is the least common size and worth asking about rather than assuming. The 20-foot is the 10×16 or 12×16 replacement above. A 40-foot container is 320 square feet, larger than any kit shed on the table, and is a workshop, a farm equipment lockup or a whole household’s contents; the 40-foot high cube adds a foot of headroom for racking. The sea can interior size chart carries the full interior dimensions and cubic capacities, and the container sizes and dimensions page has the metric figures and the reefer and 45-foot units.
Two things a shed buyer should know about container sizing that a shed guide never mentions. First, a container’s length is the only variable; the width is always 8 feet and the door is always at the end, so the layout inside is a corridor with shelving both sides, which suits equipment and boxes and suits a workshop bench less well unless a side door is cut. The shelving guide covers how the corridor is fitted out. Second, the box needs a straight run about twice its length for the tilt-deck to set it down, which is a delivery question rather than a size question, and how the tilt-deck sets a box down answers it before you order.
Who Should Buy Which
Buy the 8×10 if the biggest thing is a push mower or a snowblower and the yard is a suburban one; buy it with the double door and put the savings into a proper base. Buy the 10×12 if a riding mower is going in, or a workbench, and accept that it is one or the other; from this size up, the base is a gravel pad or a slab. Buy the 12×16 if you want a workshop in a backyard where it will be seen, and buy the best walls and roof you can, because at this size the shed is a building and will be judged as one. The Costco shed lineup, the Home Depot shed lineup, the Canadian Tire shed lineup and the Rona and Lowe’s shed lineup sort what each retailer actually stocks at each size, and the Cedarshed kit review covers the premium cedar kit whose Rancher line runs from 6×6 to 10×20.
Buy a container if the list is 160 square feet or more of things that lock, the site is rural, agricultural, commercial or a cottage lot, the ground is gravel or grass, the building has to be there this week, or you want it to still be worth something in 2036. The storage answer is the 20-foot dry box, used and wind-and-watertight from the used container rows; the workshop answer is the 40-foot high cube box, one-trip from the one-trip container rows if it is going to be cut for a side door and a window at the modification bay. Every unit is picked by a person and can be picked by you: walk the rows at 90 Morton Avenue East and choose the box by its number before any money moves, pay on delivery after it is on your ground, and have it landed anywhere in the Ontario delivery area in one to three days. Everything is sold outright; Van Blanc keeps no rental fleet and does not lease.
List over 160 square feet? Price the box once
Tell us the biggest thing going in, the grade you have in mind and your postal code, and we will send an all-in number for the container delivered and placed, usually the same day. If your shed is really an 8×10 in a fenced yard, we will say so. Or walk the shed-sized rows in Brantford and pick the unit yourself.
For the seasonal version of the same sizing question, the seasonal equipment storage guide works through what a household stores in each season and where, the container site-prep page covers the pad either building needs, and the alternatives to a container hub is the wider read for anyone still deciding what kind of building the job needs at all.
Shed Size FAQs
What fits in an 8×10 shed?
A push mower, a snowblower, two or three bikes on hooks, garden tools on a rail, camping gear and a shelf of seasonal boxes, with the patio chairs stacked in a corner. Inside it is about 7 by 9 feet once the walls are counted. It does not take a riding mower comfortably, and it needs a double door rather than a 30-inch single to be worth having.
Will a riding mower fit in a 10×12 shed?
Yes; the 10×12 is the first size that takes a lawn tractor, which is about six feet long and close to four feet wide with the deck, along the long wall with room beside it for a push mower or a snowblower. It needs a door at least four feet wide. What the 10×12 will not do is hold the rider and a usable workbench together; that is a 12×16.
How much bigger is a 12×16 shed than a 10×12?
Sixty percent more floor: 192 square feet against 120 outside, about 165 against 99 inside. Because the roof, the door and the floor system are the expensive parts of a shed and a longer wall is cheap, the price step is smaller than the space step, which is why every builder says to go one size up if the yard allows it.
Is shed size measured inside or outside?
Outside, at the outer face of the walls. Studs, sheathing and trim take roughly a foot in each direction, so a 10×12 gives about 9 by 11 feet of floor and a 12×16 about 11 by 15. Resin sheds lose a little less to the walls; wood sheds with 2×4 framing lose the full foot; metal sheds lose the least on the walls and the most at the door.
What size shed do I need for a snowblower and a mower?
An 8×10 holds a two-stage snowblower and a push mower with the bikes and tools around them. If the mower is a rider, the pair needs a 10×12. Measure the widest machine against the door before choosing the size: a two-stage snowblower is 28 to 30 inches wide and a rider 42 to 48 with the deck, and a single 30-inch door defeats both.
What size shed is the same as a shipping container?
A 20-foot container is 8 by 20 feet outside, 160 square feet, the same footprint as a 10×16 shed and between the 10×12 and the 12×16; inside it is about 148 square feet with a flat 7-foot-10 ceiling and a door the full width of the end. A 10-foot container matches an 8×10 shed’s footprint, and a 40-foot is 320 square feet, larger than any kit shed.
When is a container cheaper than a big shed?
From about 160 square feet of storage, once the kit’s base, delivery, assembly and first repair are counted, a used wind-and-watertight 20-foot container delivered finished usually costs less per square foot, locks properly and needs no maintenance schedule. Below that, in a suburban yard where looks matter, the shed is the cheaper and better building.
Sources
- Keter Canada. (2026). What Size Shed Do I Need? keter.com
- Duramax Sheds Direct. (2026). How to Choose the Right Shed Size for Your Home. duramaxshedsdirect.com
- Urban Shed Concepts. (2026). Which Shed Size is Best? 8×10, 10×12, or 12×16? urbanshedconcepts.com
- North Country Sheds. (2026). 8 x 10 Storage Sheds. northcountrysheds.com
- Wayfair Canada. (2026). Shed Sizes: How to Choose the Right Size. wayfair.ca
- Van Blanc Ent. Inc. (2026). Sea Can Sizes, Dimensions and Measurements. vbinc.ca
Reach Van Blanc in Brantford
We have been supplying shipping containers across Ontario since 1995. Our yard is at 90 Morton Avenue East in Brantford, and we deliver right across the province with payment on the day of delivery. No deposit, no upfront wires, no chase-the-paperwork.
Van Blanc Ent. Inc., 90 Morton Ave E Unit 1B, Brantford, ON N3R 7J7, 519-754-6844 (cell) or 1-888-509-6658 (toll-free).
If the shed you were sizing turned into a steel box somewhere in this page, call with the biggest thing going in and your postal code and we will tell you on the spot what is in stock and when it can land. Worth the drive for unbeatable quality, family customer service with 30 years of experience.