Complete Buying Guide: How to Choose a Used 20-Foot Shipping Container (Dry)

Why choose a used 20-foot shipping container?

The used 20-foot Dry shipping container stands out as a robust, modular and economical solution for storage, transport or conversion. Its popularity stems from a rare balance between capacity, footprint and cost. With standardized dimensions (6.06 m long, 2.44 m wide, 2.59 m high) and an internal volume of about 33 m³, it offers a floor area of 14 m², ideal for many projects. Unlike a new container, a refurbished used model provides a Corten steel structure and marine plywood floor at a significantly lower price, while maintaining excellent durability. This guide walks you step by step through choosing your used 20-foot container, highlighting technical criteria, essential checks and suitable uses.

Technical specifications to know before buying

Before you start, it is essential to master the specifications of a standard 20-foot Dry container. These characteristics are standardized by ISO (ISO 668 for dimensions, ISO 1496 for technical specifications), ensuring universal compatibility with ships, trains and trucks.

Dimensions and volume

• External length: 6.06 m
• External width: 2.44 m
• External height: 2.59 m
• Internal length: 5.90 m
• Internal width: 2.35 m
• Internal height: 2.39 m
• Internal volume: 33 m³
• Floor area: 14 m²

These dimensions are those of a standard 20-foot container. There are High Cube variants (30 cm taller) or specialized models (Reefer, Open Top, Flat Rack), but the Dry remains the most versatile for most uses.

Materials and construction

The structure is made of Corten steel, a low-alloy steel that resists atmospheric corrosion by forming a protective surface layer. This allows it to withstand weather and marine environments without heavy maintenance. The side walls and roof are made of corrugated steel sheet, providing significant structural rigidity. The floor is 28 mm thick marine plywood, a dense, moisture-resistant material capable of supporting heavy loads (up to about 28,000 kg payload). The double rear doors are equipped with standard container locks and rubber seals ensuring air and water tightness (Wind & Watertight standard).

Essential checks before purchase

Buying a used container carries risks if certain key elements are not checked. Here are the points to examine imperatively.

1. Structural condition

Inspect for perforating rust, major deformations or cracked welds. Surface rust is normal and can be treated, but deep corrosion can compromise strength. Check corners and bottom rails, often more exposed.

2. The floor

The marine plywood should not have soft spots, rot or delamination. A damaged floor can be sanded and treated, but replacement is costly. Make sure it is dry and free of persistent odors.

3. Doors and sealing

Doors should open and close without forcing. Locks should work properly and seals should be flexible and without tears. A light tightness test (closing the doors and looking for gaps) gives a first indication. For a more thorough check, a water test can be performed.

4. The CSC plate

The CSC plate (Convention for Safe Containers) certifies the container's compliance with safety standards for international transport. Check that it is present and valid. Without it, the container cannot be used for export.

5. Markings and history

The container identification number (owner, series) allows tracing its history. A container used for dangerous or food goods may have usage restrictions. Do not hesitate to ask the seller for details.

Refurbished vs. non-refurbished used: what differences?

A used container can be sold as is or refurbished. A refurbished container has been inspected, cleaned and possibly repaired to meet the Wind & Watertight (WWT) standard. This means it is airtight and watertight, suitable for dry storage and export. The price is generally higher than a non-refurbished container, but peace of mind is greater. Ensure the refurbishment includes replacing door seals if necessary and checking welds.

Uses of the 20-foot Dry container

Thanks to its modularity and robustness, the 20-foot Dry container adapts to many uses.

Professional storage

On construction sites, it serves as a living base (locker room, canteen, office). Logistics companies use it as a buffer storage unit for goods not sensitive to moderate humidity. In agriculture, it stores seeds, fertilizers or small equipment, provided adequate ventilation is planned.

Residential use

Individuals see it as an extra garage, DIY workshop or storage space for garden furniture. It can also serve as a garden shed, subject to local planning rules.

Conversion and transformation

The container can be transformed into a site office, technical room, locker room, break room, or even light housing after insulation and interior fitting. Note: steel is a thermal conductor, insulation is essential for regular use. Moreover, any structural modification (drilling, adding windows) must be done properly and can affect sealing.

Comparison with other container formats

To make an informed choice, compare the 20-foot Dry with other common formats:

• 40-foot standard: volume of about 67 m³, double. More suitable for large volumes, but requires a longer site and a suitable truck, often more expensive to move.
• 40-foot High Cube: gains about 30 cm of internal height, valuable for storing bulky but light goods, or for a conversion with a false ceiling.
• 10-foot: rarer, suitable for very restricted spaces, but its price per cubic meter is generally higher.
• 20-foot High Cube: adds height without lengthening the footprint.
• Specialized containers: Reefer (refrigerated) for perishable goods, Open Top (open roof) for top loading, Flat Rack (no side walls) for out-of-gauge loads.

The 20-foot Dry remains the most versatile and economical for most common uses.

Regulations and installation in France

Installing a container on private land is subject to certain rules. A container is not considered a hard construction under the French Urban Planning Code, but its installation may require a prior work declaration if it exceeds three months, especially if the container is visible from the public road. For residential use, even temporary, a building permit may be required. Check with your local planning department and consult the Local Urban Plan (PLU). In protected areas (classified sites, near historic monuments), additional constraints apply.

Regarding transport, the container must comply with the CSC standard and carry a valid plate. The carrier must respect loading and securing rules, including the use of twist-locks to secure the container to the chassis. For exceptional transport, prior authorization is required.

Preparing the ground for your container

A 20-foot container weighs about 2,200 to 2,400 kg empty. It must be placed on a flat, stabilized surface: concrete slabs, blocks or compacted gravel bed. Soft ground can cause differential settlement and deform the structure. Provide a slight excavation or shims to raise the container a few centimeters, to facilitate air circulation under the floor and prevent water stagnation. If the container remains in place, an anchoring system (straps, stakes or ground fixings) can be considered in wind-exposed regions. Think about accessibility: sufficient space in front of the doors for opening maneuvers and passage of a pallet truck or forklift.

Maintaining a used container to make it last

Maintaining a shipping container is simple and inexpensive. Regular cleaning with clear water and mild soap removes salt deposits and dirt. Avoid overly powerful pressure washers that could damage seals. Periodically inspect door seals and apply a silicone-based product to keep them flexible. If paint chips appear, treat them with anti-rust paint to prevent corrosion. The floor can be swept and, if necessary, treated with linseed oil or a fungicide. Regularly check fixings and locks.

Budget and return on investment

The price of a refurbished used 20-foot Dry container is generally around €1,350 (excluding transport and options). This amount can vary depending on condition, age and availability. Compared to building a traditional shelter, the container offers unbeatable value for money. Its lifespan, with minimal maintenance, often exceeds 15 to 20 years. For a professional, it represents a mobile and secure storage solution, quickly operational. For an individual, it is a functional and durable extra space.

Delivery and installation

Delivery of a 20-foot container can be done by crane truck or truck with unloading arm, allowing it to be placed on the ground without an additional crane. Check that the ground is accessible and stable. The total loaded weight (container + goods) must not exceed legal limits (44 tonnes for a 5-axle road train). For an out-of-gauge container, exceptional transport authorization is required. Transport Hosni Conteneur, based in Marseille, can advise you on delivery arrangements suited to your project.

How to secure your container against theft and intrusion

A shipping container is difficult to force, but not inviolable. The rear door, the main weak point, can be equipped with additional security devices. Here are the most common solutions.

High-security padlock

A hardened padlock, such as a "container lock" or "puck lock", attaches to the locking handles and prevents their rotation. Choose a hardened steel model, resistant to saws and bolt cutters. This type of padlock is often certified to resistance standards (e.g., Sold Secure certification in the UK).

Security bar

A lockable metal bar attaches across the entire width of the doors and blocks opening. It considerably complicates break-ins and can be coupled with a padlock. Some bars are retractable so as not to hinder opening.

Integrated locking system

More sophisticated locking kits, such as "lockboxes" that enclose the handles, offer additional protection. They are particularly recommended if the container is isolated or stores valuable goods.

Surveillance and lighting

Motion-detection lighting, a camera or a standalone alarm deter intrusions. For a remote site, an alarm system running on battery or solar panel can be considered. Finally, installing the container in a place visible from the street or a dwelling reduces risks.

Mistakes to avoid when buying a used container

To avoid regretting your purchase, avoid these common pitfalls:

1. Neglecting floor inspection: a rotten floor is costly to replace and can cause humidity problems.
2. Relying only on paint: a fresh coat of paint can hide deep corrosion. Always inspect the structure from all angles.
3. Forgetting to check the CSC plate: without it, it is impossible to export or transport the container on public roads legally.
4. Underestimating transport cost: delivery can represent a significant part of the budget, especially if the site is difficult to access.
5. Not planning insulation: if you convert the container, insulation is essential for thermal comfort and to avoid condensation.
6. Buying without seeing: even with photos, an on-site visit remains the best way to judge the real condition.

20-foot container: weight and load questions

The empty weight of a standard 20-foot Dry container is about 2,200 to 2,400 kg. Its maximum payload is about 28,000 kg, but this value can vary slightly depending on the manufacturer and year. The sum of empty weight and payload gives the maximum gross weight (about 30,480 kg for a standard 20-foot). This information is on the CSC plate and on the container door. It is essential to respect these limits for safety and road transport compliance. If you store heavy materials (tools, machines, pallets of tiles), distribute the load evenly on the floor and avoid excessive concentration points.

Where to buy a used 20-foot container with confidence

The used container market is vast, but not all sellers are equal. Choose a specialized professional, able to provide precise information on the container's condition, history and compliance. A serious seller will let you visit the container, give you an invoice and can organize transport. Beware of too-good-to-be-true ads without verification possibility. At Transport Hosni Conteneur, based in Marseille, we support you in choosing the model suited to your project and advise you on technical and regulatory aspects.

Conclusion

Choosing a used 20-foot Dry shipping container means opting for a proven, scalable and economical solution. By checking the condition of the structure, floor and doors, ensuring the CSC plate is present and respecting installation rules, you invest with peace of mind. Whether you are a construction professional, farmer, local authority or individual, this format meets most storage and conversion needs. Do not hesitate to seek expert advice to validate your choice and organize delivery in the best conditions.