Used 20ft Shipping Container (Dry): Uses, Modifications and Fit-Outs

Why choose a used 20ft Dry container?

The used 20ft Dry shipping container, often called "20' DC" (Dry Container), is a steel box designed for transporting dry goods. Its popularity among professionals and individuals comes from a rare balance: an internal volume of around 33 m³, an external length of 6.058 m and proven durability. Buying a refurbished, watertight (Wind & Watertight) used container gives you this strength on a controlled budget, while giving a second life to industrial equipment.

At Transport Hosni Conteneur, in Marseille, we offer this refurbished, inspected model with a watertightness guarantee. Whether you need secure storage space, a base for a technical room or a support for a modular fit-out, the 20ft Dry offers remarkable versatility. This article details its uses, possible modifications and the precautions to take for a successful project.

Technical specifications of a used 20ft Dry

Before considering a use or modification, it is essential to know the dimensions and materials of this container. The values below are common references for a standard 20ft Dry, compliant with ISO 668 and ISO 1496-1.

• External dimensions: approx. 6.058 m long, 2.438 m wide, 2.591 m high.
• Internal dimensions: approx. 5.898 m long, 2.352 m wide, 2.393 m high.
• Internal volume: approx. 33 m³.
• Tare weight: generally between 2,200 and 2,400 kg.
• Maximum payload: up to approx. 28,000 kg depending on specifications.
• Maximum gross weight (MGW): commonly 30,480 kg.
• Structure: Corten steel, corrugated walls and doors.
• Floor: 28 mm thick marine plywood.
• Doors: double rear doors with container locks and rubber seals.

These characteristics form the basis of any fit-out planning. The resistance of Corten steel to atmospheric corrosion and the strength of the marine plywood floor allow intensive use, provided you respect load limits and regularly check watertightness.

Common uses of a used 20ft Dry container

The 20ft Dry container is the most universal format for dry storage and general cargo transport. Its applications are numerous and vary by sector.

Secure storage

Storage is the most widespread use. Thanks to its steel structure and lockable doors, the container protects goods from weather and theft. It is used to store:

• Power tools, consumables and spare parts for construction.
• Archives, paper documents and office furniture.
• Site equipment, scaffolding, generators.
• Electronic equipment, servers, IT hardware.
• Leisure vehicles (motorcycles, scooters, quads) and DIY equipment.

For long-term storage, it is advisable to add a moisture absorber or suitable ventilation, as condensation can form inside when temperatures vary. "Wind & Watertight" sealing protects against rain and wind, but does not make the container airtight to ambient humidity.

Transport of goods

Compliant with maritime standards, the 20ft Dry can be shipped by rail, road or sea. It can be stacked up to nine units on a ship and handled by machinery equipped with spreaders or hooks suitable for the corner castings. For road transport, it must be loaded onto a vehicle respecting the weight and dimension limits of the highway code. A valid CSC (Convention for Safe Containers) plate is mandatory for sea transport.

Site office and living base

In the building and public works sector, the 20ft container is frequently used as a site office: tool storage, crew changing room or temporary office. Its compact size allows it to be placed on small footprints, and its weather resistance protects equipment. For use as a site office, a planning permission may be required depending on duration and location; it is advisable to check with the local council.

Buffer reserve in industry and logistics

Industrial companies use the 20ft Dry as a buffer zone for parts awaiting quality control, as a spare parts store, or as a temporary packaging unit. Its modularity allows it to be installed quickly on a site, without heavy works.

Retail and events

In retail, it can serve as storage for seasonal goods, or as a pop-up sales unit after a basic fit-out. Local authorities and associations use it to store event equipment, archives, or as a technical room for pumping or water treatment equipment.

Possible modifications and fit-outs

The 20ft Dry container is an excellent base for various modifications. Its 33 m³ internal volume and rigid structure allow insulation, partitions, electrical networks and ventilation to be installed. Here are the most common fit-outs.

Site office or administrative room

A container fitted out as an office provides a functional workspace on a site or isolated location. Typical works include:

• Thermal insulation of walls, roof and floor (mineral wool, spray foam, rigid panels).
• Installation of flooring (PVC, laminate, carpet) on the marine plywood floor.
• Light partitions to separate areas (office, meeting, sanitary).
• Electrical installation: panel, sockets, lighting, heating/air conditioning.
• Mechanical or natural ventilation to renew air.
• Joinery: entrance door, windows (to be cut into the walls).

These modifications require reinforced air tightness and compliance with local construction rules if the use becomes permanent.

Workshop, technical room or changing room

For a workshop, technical room or changing room, the fit-out can be simpler: minimal insulation, lighting, power sockets, workbenches or lockers. The marine plywood floor supports heavy loads, but it is advisable to protect it with a coating suited to the use (sheet metal, resin, rubber mat). Ventilation is essential to remove fumes or humidity.

Modular housing and tiny house

Converting a 20ft container into modular housing is an ambitious but achievable project. It requires:

• High-performance thermal insulation (walls, roof, floor) to prevent condensation and thermal bridges.
• Reinforced air and water tightness, with treatment of junctions.
• Water, electricity and sanitation networks, often complex to integrate.
• Openings (doors, windows) cut and reinforced with metal frames.
• Compliance with local planning rules (local urban plan, building permit).

A 20ft container offers a living area of about 13.8 m² (5.898 m x 2.352 m), suitable for a studio or spare bedroom. For larger housing, assembling several containers is possible.

Sales unit or showroom

After a careful fit-out (insulation, lighting, display window), a container can become a pop-up sales unit or showroom. Its modular structure allows it to be moved as needed, and its industrial look can be a marketing asset.

Points to check before buying a used container

Buying a refurbished used container offers excellent value for money, but a careful inspection is essential. Here are the key points to check.

Watertightness

Ask whether the container is guaranteed "Wind & Watertight". Visually check door seals, welds and any signs of perforating rust. A water test (spraying) can reveal leaks.

Structural condition

Look for major deformations, non-professional repairs or areas of advanced corrosion. The corner castings must be intact and not cracked. The roof is often neglected: check that it shows no perforating corrosion or impact deformation.

Floor

The marine plywood floor must be solid, with no soft spots or delamination. Inspect especially the corners and under the doors, where moisture can stagnate. A sound floor must not show rot.

Doors and locks

The double rear doors must open and close without forcing. Locking bars must slide without excessive play. Rubber seals must not be dry, cracked or missing.

CSC plate and markings

Check for the CSC identification plate and regulatory markings, which attest to the container's compliance for sea transport. The plate shows the manufacturing date, approval country, identification number, maximum gross weight, tare weight, payload and date of next examination.

Maintenance of a used 20ft container

A well-maintained container retains its value and functionality for many years. Maintenance is simple but regular.

• Door seals: clean and lubricate them with a silicone-based product to prevent drying and cracking. Replace them if cracked.
• Hinges and locks: grease periodically to ensure smooth operation.
• Corten steel structure: clean with clear water. For deep scratches or early rust, apply an anti-corrosion treatment and suitable paint.
• Floor: clean with soapy water; avoid high-pressure jets. For oil stains, use a suitable degreaser and rinse. Localised rot can be repaired by patching or replacing the board.
• Ventilation: to combat condensation, install ventilation grilles or use passive dehumidifiers.
• Paint: repaint every five to ten years, depending on exposure.

Regulations and transport

The use of a shipping container in France is governed by several rules. For sea transport, the CSC (Convention for Safe Containers) of the International Maritime Organization (IMO) requires a valid approval plate. Periodic examination is generally carried out every 30 months for new containers, then every 24 months for older containers, but rules may vary.

For use as a site office, if the installation period is less than three months, a prior declaration is often not necessary. Beyond that, a development permit or planning permission may be required. For permanent use (housing, office), you must comply with the local urban plan (PLU) and construction rules (DTU).

Road transport of a 20ft container requires a vehicle whose gross vehicle weight rating (GVWR) and gross train weight (GTW) are compatible with the mass transported. An empty 20ft container weighs about 2.3 tonnes; loaded, it can reach 30 tonnes. The driver must respect speed limits and signage rules for wide or heavy loads.

Comparison with other container types

The choice of a container depends on the nature of the load, weight, volume, protection and budget constraints. Here is a brief comparison.

• 40ft Dry (40' DC): internal volume of about 67 m³, double the 20ft. More economical per cubic metre transported, but requires a longer site and a suitable vehicle (semi-trailer).
• 40ft High Cube (40' HC): adds about 30 cm of internal height (approx. 2.695 m), useful for bulky but light loads, or for a fit-out with a suspended ceiling.
• 20ft High Cube: internal height of about 2.684 m, but less common on the used market.
• Open Top (20' OT or 40' OT): opening or removable roof, allows loading tall objects from above.
• Flat Rack (20' FR or 40' FR): no side walls or roof, only a reinforced floor and foldable end walls; designed for heavy or oversized loads, but without weather protection.
• Reefer (20' RF or 40' RF): equipped with a refrigeration unit and reinforced insulation for transporting perishable goods or pharmaceuticals; heavier, more expensive and requires a power supply.
• Tank container: intended for liquids and gases, with a stainless steel tank inside a 20ft frame.

The 20ft Dry remains the most universal format for dry storage and general cargo transport. Its attractive used price and availability make it a wise choice for many projects.

Conclusion

The used 20ft Dry shipping container is a durable and versatile investment. It suits many uses, from simple secure storage to modular fit-out, including general cargo transport. Its compact format, Corten steel structure and marine plywood floor make it resistant, repairable and scalable equipment. At Transport Hosni Conteneur, in Marseille, we provide refurbished and inspected containers with a watertightness guarantee. We invite you to contact us to discuss your project, check availability and arrange delivery. Whether you are a building professional, an industrial company, a retailer or an individual, we will guide you to the most suitable solution.