Buying a used shipping container—whether a compact 20FT Shipping Container or a spacious 30FT Shipping Container—is an excellent investment. However, because these units have traveled the world and withstood harsh conditions, inspecting the unit’s condition is critical to ensure it meets your needs for security, storage, or modification.
At fredemi.org, we pride ourselves on transparency, but we also want you to be a confident buyer. Here is a practical, four-point checklist for inspecting any used shipping container before you finalize your purchase.
1. Condition Grades Explained: Knowing What You’re Buying
The container’s grade is the first thing to understand, as it dictates its price and suitability for your project:
- One-Trip (New): This is the best quality, having only completed one journey from the manufacturer. It has minimal dents and is almost pristine, ideal for high-end conversions or residential use.
- Cargo Worthy (CW): Certified for international shipping, meaning it is structurally sound and fully watertight. These units are perfect for transport, serious modifications, or long-term secure storage.
- Wind and Water Tight (WWT): The most common used grade. These containers are retired from shipping but are guaranteed to keep the elements out. They will show signs of wear, surface rust, and dents, but they are highly cost-effective for stationary storage.
2. The Essential “Light Test” for Leaks
Watertightness is non-negotiable for storage. The steel walls and roof must be intact to protect your goods.
- How to Perform the Test: Step inside the container, close the doors completely, and let your eyes adjust to the darkness.
- What to Look For: If you see any small pinholes or streaks of light coming through the walls, ceiling, or floor, that means water can also get in. Even small light leaks can lead to significant condensation and moisture damage over time. If light gets in, water will too.
3. Floor Inspection: Check for Damage and Contamination
The standard flooring in shipping containers is marine-grade plywood, designed for durability. You need to verify its integrity:
- Soft Spots and Rot: Walk the entire length of the container floor, paying close attention to the corners and areas near the doors. Any soft spots indicate water damage or rot.
- Contamination (If Applicable): If you plan to convert the container into a food-grade storage unit or a habitable space, check for any foul or chemical odors. Used containers may have carried hazardous materials in the past.
4. Door and Seal Functionality: Security Starts Here
The container doors are the most complex moving part and the primary security barrier.
- Door Operation: The doors should open and close relatively smoothly, though some stiffness is expected on used units. Ensure all locking bars (typically four per door) are straight and operate properly.
- Rubber Seals (Gaskets): These seals, or gaskets, run along the entire perimeter of the doors. They must be present, intact, and pliable. Cracking, hardening, or missing sections will compromise the container’s watertight seal. A good seal is crucial for keeping out rain and pests.
By following this checklist, you can ensure that the 20FT or 30FT container you purchase from fredemi.org will be a secure, reliable solution for your project for years to come.
