Popular Shipping Container Modifications to Plan Before You Buy
Shipping container modifications are changes you make inside or outside a container to fit it to a job. Common upgrades include doors, windows, insulation, vents, lights, shelves, and paint.
A plain steel box works fine for storage. With the right upgrades, it can become an office, a shop, a food stand, or a cool, dry storage room.
Below are the most popular shipping container modifications. You’ll see what each one does and what to plan before anyone cuts steel.
Container modifications Transocean installs
Transocean Equipment Management sells and modifies new and used containers. We serve buyers in North Carolina, South Carolina, Georgia, and Virginia. Our standard options include:
- Insulation, vents, and HVAC
- Windows, skylights, and roll-up doors
- Lighting and electrical
- Flooring, shelving, and custom paint
- Lock boxes and smoke detectors
Some upgrades on this page, like plumbing and rooftop decks, need outside trades. Ask us about any item before you order.
Choose the right base container first
The box you start with shapes every upgrade. Pick the size and condition first.
- New (one-trip) containers have straight walls and clean paint. They are the best base for cuts, welds, and finishes people will see.
- Used containers cost less and suit storage with light upgrades. Dents and rust add prep work before paint or foam.
- High cube containers stand 9’6″ tall instead of 8’6″. The extra foot leaves room for ceiling insulation and lights.
Compare new shipping containers with used storage containers.
Still torn? Read whether to buy new or used. For exact sizes, see our container specifications.
Branding
If you use your container for business, you can paint or wrap it with your brand and logo. Add anything from signs to your phone number and hours.
Paint lasts the longest. Vinyl wraps and magnetic signs let you change the message as needed. Branding helps any business that needs to be seen, from real estate to food.
Interior paint
New containers leave the factory with a light gray coating on the inside walls. It guards the steel against rust, but it is not a finished look.
Many people repaint the inside when the unit will be an office, food stand, or restroom. That covers any use where guests, customers, or staff spend time inside.
Pick a paint made for metal. Clean the walls and prime any rusty spots first. For color and décor ideas, see our guide to decorating the interior of your shipping container.
Flooring
Most container floors are about 1.1 inches (28 mm) of marine plywood. Makers treat this wood with bug killer so containers can pass biosecurity rules in countries like Australia.
That is fine for storage. For an office, classroom, or living space, seal the plywood or cover it before you lay a new floor.
You may want a better floor if your unit will be a meeting room, mobile office, or training room. Vinyl plank with a wood look is a popular choice.
A mobile restroom needs a tougher floor. Slip-resistant vinyl is easy to clean. For a portable gym, rubber mats soak up impact and protect the plywood.
Doors and windows
Doors and windows are the cuts buyers ask for most. They change how people and gear get in, and how much light the space gets.
Personnel doors
A personnel door, or man door, lets you walk in without opening the heavy cargo doors. Offices and shops use one every day.
Most are standard 36-inch steel doors set in a welded steel frame. Read more about choosing the right exterior door for your shipping container.
Roll-up doors
Roll-up doors open a wide side or end wall for carts, mowers, ATVs, and pallet jacks. Retail stands and farms use them often. The opening needs heavy steel framing because it removes a large piece of wall.
Windows and skylights
Windows add daylight and fresh air to offices and shops. Each one sits in a steel frame welded into the wall.
Skylights bring in light without using wall space. Seal every roof opening well, since the roof is where containers leak first.
Insulation, ventilation, and HVAC
Steel moves heat fast. A bare container gets hot in a Southern summer.
In cool weather, warm inside air meets cold steel and turns to water. That moisture drips on stored goods and speeds up rust.
Insulation
Closed-cell spray foam is a common choice for containers. The Department of Energy says closed-cell foam has a higher R-value and blocks moisture and air leaks better than open-cell foam. It also costs more.
The DOE adds that foam must sit behind a fire barrier equal to half-inch drywall. Rigid foam panels and batts in stud walls cost less. Learn more in our shipping container insulation guide.
Vents and fans
Most containers have a few small factory vents. Extra louvered vents or roof vents move damp air out. They matter most for hay, feed, tools, and anything that can mold or rust.
See what to know about shipping container vents.
Heating and air conditioning
A wall AC unit or mini-split keeps an office or shop usable all year. The installer cuts and frames the opening, then seals it against weather. A licensed HVAC tech should hook up the unit.
Mobile office upgrades
If your container will be an office, add the items that make work easier. Think laminate countertops, chairs, whiteboards, file cabinets, and shelves. A shipping container partition can split one unit into an office and a storage room.
For floor plans, browse our sample layouts for your mobile office. For a step-by-step build, read how to transform a container into an office.
Plumbing
If you run a food business out of your container, or need a bathroom or break room, you can add plumbing. Options include a sink, fridge, stove, and counter space for small appliances.
Plumbing needs holes through the floor or walls, a drain plan, and a licensed plumber. Your county may require a permit and an inspection.
Lighting
For spaces that need more light, add anything from recessed lights to pendant lights. LED lights over personnel doors help at night. For security, motion sensors turn lights on when someone walks up.
Wiring for lights and outlets should be done by a licensed electrician to local code.
Rooftop decks
Why not make good use of the space above the container? A rooftop deck gives you a spot to watch over a work site or host guests.
Plan it with care. Container roofs are thin steel. They are not built to hold a deck, people, and furniture on their own.
A rooftop deck needs its own frame that carries weight down to the corner posts. Have an engineer approve the design.
Locks
If your container will hold things of value, get locks that go beyond the standard ones. Choices range from cargo door locks to security swing arms to lock boxes.
A lock box shields your padlock from bolt cutters. Compare options in our guide to shipping container locks.
Miscellaneous modifications
There is no shortage of other upgrades. More popular options include:
- Windows
- Roll-up doors
- Skylights
- Heat and AC units
- Security bars
- Vents and fans
- Framing and insulation
- Electrical
- Partitions
- Solar panels
- Shelving
How modifications affect container strength
A container gets its strength from its frame. Corner posts, top and bottom rails, and corner castings carry the load. The ribbed walls stiffen the box.
Every cut takes away some of that steel.
- Frame every opening. A good fabricator welds a steel frame around each door, window, or vent cut.
- Leave the frame alone. The 2021 International Building Code bans cutting or notching rails, corner castings, and posts for single containers using its simplified design path (IBC Section 3115).
- Plan for ground use. Large cuts reduce how much weight the container can carry on top. A heavily modified unit stays on the ground.
- Check the steel first. Look for rust at the base rails and door frame before you pay for upgrades.
Learn what affects the structural integrity of a shipping container. Then see how to keep your storage container from rusting.
Permits and building codes for modified containers
Rules depend on how you use the container. Storage units face fewer rules than offices, shops, or homes.
The 2021 International Building Code added Section 3115 for containers used as buildings. It asks for the box’s data and a review of its strength.
South Carolina’s 2021 building code includes this section and took effect on January 1, 2023.
Keep the safety approval (CSC) plate on the door. Code officials may ask for its data.
Call your county building office before you order. Check zoning and HOA rules too. Georgia buyers can start with are container homes legal in Georgia.
What affects the cost of container modifications
Prices vary a lot from job to job. These factors drive most of the cost:
- Number and size of cuts. A roll-up door costs more than a vent because it needs more steel framing.
- Container size and condition. A 40-foot unit takes more insulation and paint than a 20-foot unit. Rust repair adds labor.
- Insulation type. Spray foam costs more than panels or batts.
- Outside trades. Wiring, plumbing, and HVAC add licensed labor and permits.
- Finish level. A storage upgrade costs far less than a finished office.
- Delivery distance. See how shipping container delivery works.
Ask for a line-item quote. It lets you add or drop upgrades to fit your budget.
Benefits of shipping container modifications
Upgrades let you build the exact space you need for work, home, or play. A modified container is:
- Customizable to your use
- Often cheaper and faster than a site-built shed or office
- A reuse of an existing steel structure
- Safe and durable
- Weather and rodent resistant when doors and seals are in good shape
- Convenient to place on your site
- Personalized
- Comfortable once insulated and ventilated
A shipping container is mobile, so it works well for short-term uses. When the job ends, you can move it to a new site.
Make your container your own with a few simple or complex changes that fit your needs and budget.
The many uses of shipping containers
People modify containers for all kinds of reasons. You can convert one for almost any use, such as:
- Ticket booth
- Security booth
- Hydroponic container farm
- Garage
- Tiny home
- Sports equipment locker
- Pop-up café
- Pool
- Shed
- Theater
- Bistro
- Field hospital
- Studio
- Sauna
- Art gallery
- Disaster shelter
- Student housing
- Camper
- Playhouse
- Lab
- Backyard pool house
- Guest house
- Indoor garden
Shipping container modification FAQs
How much does it cost to modify a shipping container?
It depends on the number of cuts, the insulation type, and whether you need wiring, plumbing, or HVAC. A lock box costs far less than a full office build. Ask for a line-item free quote to price your exact project.
Do modifications weaken a shipping container?
Yes, every cut removes some steel. Openings framed with welded steel keep the container sound for ground use. Never cut the corner posts or rails.
Can you modify a used shipping container?
Yes. Pick one with straight walls, a solid floor, and little rust at the base. Our container condition guide explains each grade.
How can you make a shipping container look better?
Start with fresh exterior paint in your brand colors. Add windows, a personnel door, and exterior lighting. Wood or composite trim and planters soften the steel look.
Do I need a permit to modify a shipping container?
Storage use often needs fewer approvals than an office or home. Occupied spaces may need a building permit under your state’s code. Check with your county before you order.
Contact Transocean Equipment Management
Want to learn more about the upgrades we offer? Contact us for a free price quote at (910) 483-7828. We will walk you through the choices for your new or used shipping container.
