Shipping containers are versatile. As well as for shipping, they’re also used as storage facilities, on-site offices, and even for converting into living spaces.
The lifespan of a shipping container depends on how you use it, what environment it’s in, and whether it’s properly maintained. Find out what shipping containers are made of – and how to make them last longer.
Shipping container basics
Before we get into the details, let’s take a look at the different types of shipping containers.
Types of shipping containers
- Standard or dry containers are the most common type. They’re available in a range of sizes. 20ft and 40ft containers are the most common, but they can be anything from 8ft to 45ft.
- High cube containers are the same length as standard containers, but a foot taller.
- Specialised containers have additional features such as refrigeration, COSSH chemical storage, open sides, or an open top. Specialised containers might have a different lifespan from standard or high cube containers depending on their specifications.
What are shipping containers made of?
Most containers are made of Corten steel – a material also known as weathering steel because it can stand up to corrosion and rust. The steel is usually coated with paint and primer for extra protection from dampness and salt.
Shipping container doors are also made from steel, with extra rubber or silicone gaskets to keep water out. Most storage containers have wooden floors which are treated to resist dampness, rot, and insect damage.
Containers also have special features to make them easier to move and stack. Steel blocks in each corner of the container, called corner castings, are used to lift and secure containers during shipping. There are metal locking mechanisms to keep the container secure while it’s moved around.
Some specialist containers also have insulation or ventilation to control the climate inside.
Want to know more about what shipping containers are made from? Learn about the different parts and materials used both inside and outside these robust structures that contribute to a shipping container’s strength and durability in our detailed article: Inside the Steel Walls: What Are Shipping Containers Made Of?
Average lifespan of shipping containers
Shipping containers are tough, low maintenance, and last for a long time. With the right maintenance, they can last for 35-40 years. When they’re converted for construction, they can last even longer – up to 50 years.
However, environmental conditions matter. Shipping containers at sea only have a lifespan of 10-12 years. Once they’re retired back on shore, they can last a further 25 years with repairs and maintenance.
Factors that affect the lifespan of a shipping container
The lifespan of a shipping container is affected by a number of different factors, including the quality of the steel, the environment, and how it’s used.
How it’s used
Containers that are used for shipping endure a lot of wear and tear. They’re often moved, lifted, and stacked, putting strain on the joints and doors. However, containers which are used for static storage can last a lot longer.
Location and foundation
Containers last a lot longer when they have the proper foundations. That means a level, stable surface, with a barrier between the container and damp soil. Keeping containers away from direct sunlight and standing water also extends their lifespan.
Weather conditions
Extreme conditions can weaken and warp steel containers. Freezing cold, high heat levels, salt water, and direct sunlight will all shorten a container’s lifespan.
Damage and dents
Shipping containers can easily be damaged during handling or transport. But even small dents can damage the structural integrity of a container, or reduce its protection from rust.
Regular maintenance and repairs
Containers should be inspected and repaired regularly so that the damage can’t take hold. Simple upkeep like removing rust and repainting containers can make them last much longer.
How to make your shipping containers last longer
When you purchase a shipping container, ask how old it is and where it’s been used. Check right away for any dents, damage, or chips.
The biggest threat to a container’s lifespan is moisture, especially salt water. You can reduce moisture exposure by:
- Storing containers off the ground on a concrete, asphalt, or gravel pad.
- Reducing internal condensation, also known as “container rain”.
- Checking regularly for rust and chipped paint.
Pick a suitable storage location
Your shipping container will last longer if it’s in the perfect spot. You’ll need somewhere that’s sheltered from direct sunlight, rain, wind, and flooding.
Access matters, too. You need a clear space around the container to load and unload it. Consider adding fencing, CCTV, or security personnel to protect the container from theft or vandalism.
Build a stable foundation
Place your container on a level surface to minimize stress on the joints. A pad of gravel, asphalt, or concrete underneath will protect it from moisture damage.
The container should be secured in place with anchor bolts or twist locks. You’ll need to check the pad and locks regularly, as well as the container itself, for any signs of wear and tear.
Proactively maintain your shipping container
Maintenance is the key to making your container last longer. Here are the basics to cover.
- Check the level of the container and re-level the foundation if necessary.
- If the container has climate control, check and replace the A/C filter according to the manufacturer’s instructions.
Remove any rust
Check for rust regularly – even small patches can have a big impact. Remove rust with a wire brush or sandpaper.
Regularly paint your container
Inspect the paint and touch up any chips or rust patches. Use specialised shipping container paint that is designed to protect metal from harsh weather conditions.
Reduce internal condensation
Don’t forget to check the inside of the container as well as the outside. Inspect rubber seals on doors, windows, and vents to make sure they’re sound, and check the level of internal condensation.
Lubricate your door hinges and joints
Lubricate door hinges and joints so that they move easily. Look for a lubricant spray that will also protect them from rust and corrosion.
If you’ve checked the hinges but the door is still difficult to open, check the level of the container. You might need to re-level the foundation.
Ensure the structural integrity of the roof
Container roofs are not designed to take a lot of weight. Check the roof regularly and remove any debris that builds up. If you notice any major dents, fill them with a sealant such as caulk to prevent roof leaks, and touch up with protective paint as necessary.
What to do when your shipping container reaches its lifespan?
If you inspect and maintain your container on a regular schedule, then you’ll know when it’s reached the end of its lifespan. Extensive rust, holes, twisting, or bowing are all signs that the container is beyond repair.
Disposing of your shipping container
It’s important to dispose of an old shipping container properly to avoid any environmental damage. As containers are made of steel, it means they can be usefully recycled. Search online for container recycling programmes near you, or check whether your local scrapyard or dump will accept them.
The bottom line
With the right treatment, shipping containers can last for up to 40 years and more. You can get the most out of a shipping container by inspecting it frequently and keeping up with repairs.
If you have any questions about buying a shipping container or need more information about how long they might last, don’t hesitate to get in touch with our team of professionals. We’re here to help you understand everything you need to know about shipping container durability and assist you in making the right purchase.
FAQs
Are used shipping containers safe?
You should always inspect a shipping container before buying or using it. While shipping containers can last decades, they need regular upkeep to keep them safe.
Do shipping container homes rust out over time?
Shipping containers are made from weather-resistant steel and treated with anti-corrosion paint and primer. When they’re converted into homes, they’ll be checked and treated again.
However, there’s still a risk of rust. You should inspect your shipping container home regularly, remove rust, and touch up paint whenever chips appear.
Do shipping containers leak?
Shipping containers in good condition will not leak. You can reduce the risk of leaks by keeping the container in an appropriate location, removing rust, renewing the paint, and sealing any dents.
What paint is used on shipping containers?
Shipping containers are treated with primer and paint to protect them from rust and corrosion. Always use specially made container paint to keep them in good condition.
