Comparing 20ft and 40ft Container Homes: Which Is Right for You?
Container homes have come a long way from their industrial shipping roots. What started as an experimental housing solution has become a legitimate option for people looking for affordable, portable, and surprisingly stylish living spaces. But one of the first decisions you'll face is simple: do you need a 20ft or 40ft container?
The difference isn't just about size. Each option comes with its own cost structure, transport considerations, and design possibilities. Getting this choice right from the start saves you money and headaches later.
Understanding the Basic Dimensions
A 20ft shipping container gives you about 160 square feet of floor space. The external dimensions are 20ft long, 8ft wide, and typically 8.5ft high. Inside, you're working with roughly 19ft by 7.7ft once you account for the corrugated walls.
A 40ft container doubles that length. You get about 320 square feet to work with. The width and height stay the same, just stretched out to 40ft long.
Here's what that looks like in practical terms:
Container size guide
Factory Fit Homes · Perth, WA · factoryfithomes.com.au
| Size | Floor space | Best for | Typical use |
|---|---|---|---|
20FT |
160 sq ft | Singles, couples, offices | Studio living, home office, granny flat |
40FT |
320 sq ft | Small families, workshops | One-bedroom home, workspace, retail pop-up |
Both come in standard height (8.5ft) or high cube versions (9.5ft). That extra foot of ceiling height makes a surprising difference in how the space feels. Most people converting containers into homes opt for high cube if they can get them.
Cost Differences That Actually Matter
A 20ft container home costs less upfront. But the cost difference isn't always as dramatic as you'd think once you factor in everything.
The container itself runs cheaper. In Australia, you might pay $3,000 to $5,000 for a used 20ft container in decent condition versus $5,000 to $8,000 for a 40ft. New containers cost significantly more, but most people building container homes go with used ones that are wind and watertight.
Where it gets interesting is the fitout cost. Insulation, electrical, plumbing, windows, doors and interior finishing costs don't scale linearly. You still need a kitchen and bathroom whether you have 160 or 320 square feet. The per-square-foot cost often works out better with a 40ft container because you're spreading those fixed costs over more space.
Transport and site preparation can swing either way. A 20ft container is easier to manoeuvre onto tight blocks and requires a smaller crane or forklift. A 40ft container needs more space to deliver and position. If your site has access issues, that 20ft option starts looking more practical regardless of cost.
Space and Layout Considerations
This is where personal needs really matter. A 20ft container home works brilliantly for specific uses but feels cramped if you're trying to fit in too much.
The 160 square feet in a 20ft container can comfortably hold a studio layout with a combined living and sleeping area, a small kitchen, and a bathroom. It's tight but functional. Think of it like a well-designed tiny home.
Everything has to earn its place. The layout options are limited by the narrow 8ft width. You're essentially working with a long hallway that you need to break into zones.
Most people put the bathroom at one end, kitchen along one wall, and use the remaining space for living and sleeping. It works, but you can't really separate activities.
A 40ft container gives you room to breathe. You can create actual separate areas. A bedroom with a door. A defined living space. A kitchen that doesn't feel like a galley on a submarine.
When 20ft Makes Perfect Sense
Some uses genuinely suit a 20ft container better.
Home offices and studios. If you're building a backyard workspace separate from your main house, 20ft is plenty. You get a dedicated professional space without the cost of a full granny flat.
Guest accommodation. A 20ft container makes an excellent guest retreat. It's self-contained, private, and comfortable for short stays without being expensive to set up.
Portable or temporary housing. The smaller size makes transport easier. If you need to move the home later or you're setting up temporary accommodation on a worksite or rural property, the 20ft is more practical.
Tight urban blocks. In cities like Perth where backyard space is limited, a 20ft footprint fits where a 40ft simply won't.
When 40ft Is Worth the Extra Investment
A 40ft container becomes the better choice when you need this to function as a primary residence or long-term living space.
The ability to separate sleeping from living areas matters for daily comfort. You can have people over without them sitting on your bed. You can close a door for privacy or quiet.
These things sound minor until you're living in the space full time.
Families with kids need the extra room. Two people can make a 20ft work. Add a child and you're constantly stepping over each other. The 40ft gives enough space for bunk beds, storage, and a small play area.
If you're planning to rent the space out, a 40ft container home rents for significantly more than a 20ft studio. The rental return often justifies the higher build cost within a few years.
Mobility and Site Flexibility
Container homes get marketed as portable, but that portability has limits. A 20ft container is easier to move, but it still requires a truck with a tilt tray or a crane. You're not hooking it to your car and driving off.
The real advantage of the smaller container is fitting it into tricky locations. Narrow side access. Properties with overhead power lines. Steep driveways. A 40ft container simply won't go where a 20ft can squeeze through.
That said, most people who build a container home aren't actually planning to move it. The portability is more about the construction method than regular relocation. Both sizes can be built off-site in a factory, transported complete or near-complete, and craned onto stumps or a slab foundation.
If genuine mobility matters, consider whether you actually need a container home at all. Purpose-built tiny homes on trailers might serve you better.
Building and Council Approval
Both 20ft and 40ft container homes need council approval in most Australian councils. Don't believe anyone who tells you a container home is just a shed you can stick in your backyard without permits.
The approval process treats them like any other habitable dwelling. You'll need plans from a draftsperson or architect, engineering certification, and compliance with the Building Code of Australia. The size of the container doesn't change that requirement.
Where size matters is in zoning classifications. Some councils have minimum dwelling sizes, typically around 50 square metres. A single 20ft container might fall short. A 40ft container at about 30 square metres also falls short unless you add a deck or verandah to meet the minimum.
Check your local council's planning scheme before committing to either size. Some areas restrict secondary dwellings to specific sizes or require minimum setbacks that rule out certain container placements regardless of length.
Making the Final Call
The choice between 20ft and 40ft comes down to how you'll actually use the space and what your site allows.
Go with a 20ft container if you need a home office, studio, guest accommodation, or you're building solo and want to keep costs tight. It's also the right choice if site access is genuinely difficult or you value the lower upfront investment.
Go with a 40ft container if this is your primary home, you're housing more than one person long-term, or you want flexibility for separate living zones. The extra cost usually pays off in livability and rental value if that's part of your plan.
Either way, work with builders who understand container conversions. The construction methods differ from traditional building, especially around insulation, condensation management, and structural modifications. Factory Fit Homes specialise in this exact type of project and can walk you through what works best for your situation and site.
If you're ready to explore what's possible with container homes, have a look at what Factory Fit Homes builds and get in touch to discuss your project at https://www.factoryfithomes.com.au/.
Frequently Asked Questions
Can I join two 20ft containers instead of using one 40ft container?
Yes, and this is actually a popular approach. Joining two 20ft containers gives you the same floor space as a 40ft but opens up layout options. You can create an L-shape or place them side by side for a wider footprint.
The trade-off is higher cost for the second container and more structural work to join them properly.
How much does it cost to fully fit out a container home in Australia?
A basic 20ft container home fitout typically runs $30,000 to $50,000 including the container itself. A 40ft container home ranges from $60,000 to $100,000 depending on finishes and inclusions.
High-end custom fitouts cost more. These figures include insulation, electrical, plumbing, kitchen, bathroom, and flooring but not site preparation or council fees.
Do container homes get too hot in Australian summers?
Only if they're poorly insulated. Proper spray foam or rigid board insulation plus reflective barriers keep container homes comfortable year-round. The steel shell conducts heat, so insulation isn't optional in Australia.
Most professional container home builders also add ventilation, ceiling fans, and split system air conditioning as standard.
Can you get finance for a container home?
Getting a traditional home loan for a container home is harder than for brick and tile, but not impossible. Some lenders classify them as non-standard construction. Your best options are usually construction loans, chattel mortgages, or personal loans.
Having detailed plans, council approval, and a registered builder improves your chances significantly.
How long does a container home last?
A properly converted shipping container home lasts 25 to 30 years or more with good maintenance. The steel structure itself is incredibly durable. The lifespan depends more on how well it's been sealed, insulated, and protected from rust.
Regular repainting and checking seals around modifications extends the life considerably.
