Container Office Layout: Plans for 10, 20 and 40 ft Units

The best container office layout starts with the interior you actually get, not the nominal length on the spec sheet. A container is 8 feet wide outside and about 7 feet 8 inches wide inside, so every plan is a long, narrow room. Layouts that work put the door, desks and storage in a deliberate order along that single axis. Below are the floor plans we see most often for 10, 20 and 40 ft units, the numbers behind them and the code and site checks that decide whether a plan can be used.

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TL;DR

A container office is a narrow rectangle, so plan in zones along its length: entry, work area, then storage or meeting space.
A 20 ft unit has roughly 148 sq. ft. of floor before insulation and walls, and a 40 ft unit about twice that. Insulation, partitions and HVAC take some of it back.
A 10 ft unit suits one person, a 20 ft unit suits one to three people with or without storage, and a 40 ft unit supports reception, private offices and a meeting room.
Delivery does not equal approval. Zoning, foundation, anchoring, exits and utility connections still go through your local building authority.
Settle the layout before you order, so doors, windows, power and HVAC are fabricated where the plan needs them.

Start with the real interior dimensions
How many people fit?
Container office floor plans that work
Layout rules that save rework
Separate storage from workspace
Approvals come before the layout is final
Jobsite office layouts
Our perspective
Order a container office built around your plan
Frequently asked questions
Sources

Start with the real interior dimensions

Standard freight containers share an external width of 8 feet and come in 10, 20 and 40 foot lengths. Heights are 8 feet 6 inches for a standard unit and 9 feet 6 inches for a high cube. Interior width is about 7 feet 8 inches, and the interior length runs a few inches shorter than the nominal length, according to the carrier container specification. The same document lists a 20 ft box at about 19 feet 4 inches inside.

Multiply 19 feet 4 inches by 7 feet 8 inches and you get roughly 148 sq. ft. for a 20 footer. That is an estimate of the bare shell. Once you add insulation, wall finishes, a partition and ducting, the usable floor and the clear width shrink, so a desk plus a walking path is tighter than it looks on paper.

Unit	Approx. interior floor (bare shell)	Realistic use
10 ft	A bit under 75 sq. ft.	One workstation, a small supervisor office, a gate or security booth
20 ft	About 148 sq. ft.	One to three workstations, or an office plus a storage room
40 ft	About twice the 20 ft figure	Reception, two or three private offices, a meeting room

The 10 ft and 40 ft figures are our arithmetic from the same width and nominal lengths, so confirm exact interior sizes for the specific unit you choose. For a fuller size breakdown, see our container dimensions size guide.

A high cube adds 12 inches of height. In an office that matters more than people expect: it leaves room for a drop of ductwork or an insulated ceiling without making the room feel low.

How many people fit?

There is no single national rule for desks per container, but safety manuals give a useful ceiling. The U.S. Army Corps of Engineers requirements, for example, point to minimum floor space per occupant and ceiling height in units that house personnel, with figures such as 50 sq. ft. per person and a 7 ft 6 in. ceiling cited for certain work camps. Those figures are for a different kind of facility, so treat them as a sanity check, not as your legal limit.

On that benchmark, a 20 ft unit is comfortable for two or three people with desks and no storage partition. Put a storage room in the same box and plan for one or two. Your local code and your use group decide the real occupant load.

Container office floor plans that work

These are layout patterns, not product specifications. Any of them can be built on a new or used container with fabrication, and all of them assume a door on the end or long side, a window or two, and wall-mounted climate control.

1. The 10 ft single workstation

The door sits on the short end or the long side near the front. A desk runs along one long wall, with a shelf above it and a chair that pulls back toward the door. There is no room for a meeting table, so this layout works as a gate office, a site supervisor desk or a ticket booth. Our guide to the 10 ft container office goes through details.

2. The 20 ft open office

A door near one end, desks along both long walls and a clear aisle down the middle. Two to three workstations fit, and a window on each long wall keeps the room from feeling like a corridor. Place the HVAC unit and the electrical panel on the same short wall so wiring stays short and furniture is not blocked. See the 20 ft office container for the standard configuration.

3. The 20 ft office and storage combo

A partition splits the box, typically with the office near the entry and a lockable storage room at the far end with its own roll-up or swing doors. The office side gets insulation and climate control, and the storage side can stay simpler. This is the most common choice for contractors, who need a desk for plans and permits and a secure place for tools. We cover it in detail in the 20 ft office combo and in our guide to offices with storage.

4. The 20 ft office with a private room

One end becomes a small enclosed office with a door, and the other end stays open for a shared desk or a visitor chair. It gives a manager a place for confidential calls without a second unit. The compromise is that both rooms end up narrow, so keep furniture slim and avoid a swinging door where a sliding or pocket door would do.

5. The 40 ft reception and offices plan

A 40 ft unit supports a real sequence of rooms: entry and reception, an open work area, one or two private offices, and a meeting room or break area at the back. A common refinement is a corridor along one long wall with doors off it, though the corridor costs width, so some plans skip it and run offices in a row. Our 40 ft floor plans and layouts and the 40 ft office container page show the options.

6. Two units joined

When one box is not enough, two 20 ft or 40 ft units can be placed side by side with an opening cut between them. That removes the narrow-room problem, but the opening is structural work, so it needs engineering and a permit discussion before fabrication, not after delivery.

Layout rules that save rework

Put the door where people need to enter, then plan around it. A door swing eats floor in a room 7 feet 8 inches wide. Choose between inward, outward, sliding or a double door early.
Zone along the length. Public or visitor area first, work area second, storage or private room last.
Group the mechanicals. Keep the HVAC, electrical panel and outlets on as few walls as possible.
Use both long walls for light. Windows on opposite walls give cross light and a second look at the site or the yard.
Plan insulation before furniture. Wall build-up reduces interior width, so check desk depths against the finished dimension, not the shell.
Keep the path clear. A straight aisle to the door matters for comfort and for exit rules.
Think about the move-in. If you are moving an existing team and equipment into the unit, office relocation services can help schedule the move around your operating hours.

Separate storage from workspace

If the unit holds anything flammable, the layout has to reflect it. Fire safety guidance for temporary buildings stresses that no temporary building may block a means of exit, which in a one-door container means the aisle must stay open. Paints, fuels and other combustibles do not belong beside desks. If your job involves them, plan a separate unit rather than a partition. Our hazmat containers and modifications are built for that kind of storage so the office stays an office.

Approvals come before the layout is final

A delivered container office is not automatically a legal one. Cities typically treat a repurposed container as a structure. The City of Portland’s building code guide for cargo containers says containers may be installed on private property for any use the building and zoning codes allow, provided they meet all applicable requirements. Rules differ by city and county, so call your building department before you commit to a plan.

The items to confirm:

Zoning and use. Is a temporary or permanent office allowed on the parcel?
Foundation and site work. Permits often attach to the foundation and utility connections, not just the box.
Anchoring. Temporary offices on construction sites are expected to be tied down against wind and seismic loads, as the Army Corps of Engineers manual describes.
Exits and fire safety. Extinguishers, clear exits and clearances around any exhaust piping.
Spacing. Some state rule proposals, such as Oklahoma’s proposed building code rules, set a minimum distance from adjacent structures for stand-alone units.

Jobsite office layouts

On a construction project, the layout of the box is only half the plan. Public specifications often require a layout of field offices, access roads and utilities to be submitted and approved, and some set occupancy within 15 days of the Notice to Proceed. That timeline works against anyone who orders after award. Decide the floor plan, the placement and the power source while bids are still being prepared.

For most jobsites a 20 ft office-and-storage combo near the gate does the work: the office faces the work area for visibility, and the storage end faces the laydown yard. Larger projects add a 40 ft unit for meetings with subcontractors and inspectors. Our jobsite office planning guide walks through placement, power and access.

Our perspective

We have delivered over 30,000 containers across 48 states, and the layout conversation nearly always goes the same way. Customers start with the number of desks. The ones who are happy a year later started with the workflow: who comes in, what gets stored, what has to stay locked and where the power and the HVAC will physically sit.

Three habits we recommend. First, choose the size by the work, not the price: an overcrowded 20 ft unit costs more in lost time than the step up costs in money. Second, put storage in a separate zone with its own door whenever tools, parts or inventory are involved. Third, ask about permits at the same time you ask about the floor plan. Turnkey means the unit arrives ready to use as built. It does not mean the site, the foundation or the approvals are done for you.

We build offices on new and used containers with custom doors, windows, insulation, HVAC and electrical, and the customization tool lets you set those before checkout.

— Conexwest

Order a container office built around your plan

When the layout is settled, you can browse office containers for sale, choose a size and configure doors, windows and interior options online. If you need a separate secure room for storage, add a second unit from our shipping containers for sale range, or rent one through storage container rentals. Tell us the delivery location and we will confirm access for the truck before it ships.

Frequently asked questions

What is the best container office layout for two people?

A 20 ft unit with desks along opposite long walls and a clear aisle down the middle works well. Keep the door and the HVAC on the same short end so neither blocks a desk. If you also need storage, partition the far end and plan for two workstations in the remaining space.

How big is a 20 ft container office inside?

A standard 20 ft container is about 19 feet 4 inches long and 7 feet 8 inches wide inside, according to the carrier specification. That is roughly 148 sq. ft. before insulation and partitions. Finished interior dimensions will be smaller.

Can I fit a bathroom in a container office?

Yes, in most 20 ft and 40 ft plans a small restroom fits at one end, but it adds plumbing, which means water, drainage and permit questions. On a 20 ft unit it takes a meaningful share of the floor, so most buyers reserve it for 40 ft plans or place a separate facility on site.

Do I need a permit for a container office?

Usually yes, though it varies by city and county. Many jurisdictions treat the unit as a structure and require approvals for use, foundation, anchoring and utility connections, as in Portland’s cargo container guidance. Ask your local building department before you order.

Sources