How to Keep Rust Off Your Shipping Container (A Practical Guide)
Rust is the biggest threat to your shipping container’s durability. If left unchecked, corrosion eats through the steel, creating weak spots, holes, and leaks. Even though containers are built with tough, weather-resistant materials, they are not rust-proof, especially if exposed to moisture for long periods.
But here’s the good news: you can prevent rust with regular maintenance and a few simple steps. Whether your container is for storage, shipping, or a modified structure, these tips will help keep it in top condition for years to come.
1. Keep It Dry (Water = Rust!)
Why? Water is the #1 cause of rust. Whether from rain, humidity, or standing water, prolonged exposure will lead to corrosion.
How to prevent it:
✔ Choose a dry, well-drained location for your container.
✔ Inspect for water pooling around or on top of your unit after heavy rain.
✔ Wipe down any standing water inside or outside the container.
✔ Install a dehumidifier or moisture absorber inside if humidity is high.
2. Elevate It Off the Ground
Why? If your container sits directly on dirt, grass, or wet ground, it will absorb moisture from below, leading to rust and warping.
How to do it:
✔ Place your container on a solid, level foundation—such as concrete slabs, railroad ties, or gravel pads.
✔ Leave at least 6 inches of clearance underneath to allow air circulation and prevent moisture buildup.
3. Fix Dents & Roof Damage Immediately
Why? Dents collect rainwater, speeding up rust formation. The longer water sits in these dents, the worse the rust will get.
How to fix it:
✔ Use a jack and wooden block to gently push dents out from the inside.
✔ If dents can’t be popped out, seal them with waterproof paint or rust-resistant coatings.
✔ Make sure the roof is slightly angled or reinforced so water runs off instead of pooling.
4. Regularly Clean & Inspect Your Container
Why? Dirt, mud, and grime trap moisture and speed up rust formation. A dirty container is more likely to develop problems.
How to maintain it:
✔ Wash your container every 3–6 months with a garden hose or pressure washer.
✔ Use mild soap and a scrub brush to remove stuck-on dirt.
✔ After washing, inspect for any rust spots, scratches, or chipped paint.
✔ Repaint areas where the protective coating has worn off.
5. Apply a Rust-Proof Coating
Why? Shipping containers come with a protective paint layer, but over time, this wears off. Adding extra protection will extend its life significantly.
Best coatings to use:
✔ Rust-proof primer – great for preventing new rust.
✔ Marine-grade paint – resists salt, water, and humidity.
✔ Corrosion-inhibiting spray – an easy solution for hard-to-reach areas.
How to apply it:
✔ Sand off existing rust and clean the surface.
✔ Apply a rust-proof primer and let it dry.
✔ Finish with two coats of protective paint.
6. Improve Ventilation to Prevent Condensation
Why? Containers that are sealed too tightly can develop condensation inside, leading to rust on the interior walls and ceiling.
How to fix it:
✔ Install air vents or a small fan to promote airflow.
✔ Use desiccants or moisture-absorbing materials inside.
✔ Avoid storing wet items inside the container.
7. Check Doors & Seals for Leaks
Why? Door seals keep moisture out. If they are cracked, broken, or clogged with dirt, water can seep inside.
How to maintain doors & seals:
✔ Inspect rubber door seals every few months and replace them if cracked.
✔ Lubricate door hinges and locks to prevent rust.
✔ Make sure doors close tightly without gaps.
8. Remove Rust Spots Immediately
Why? Small rust spots spread fast if ignored. Removing them early prevents major damage.
How to remove rust:
✔ Scrub the rust spot with a wire brush or sandpaper.
✔ Wipe clean with a damp cloth.
✔ Apply a rust converter or anti-corrosion primer.
✔ Repaint the area with rust-resistant paint.
9. Use a Tarp or Roof Cover for Extra Protection
Why? If your container is exposed to heavy rain, snow, or hail, a cover helps protect it from the elements.
How to cover it:
✔ Use a thick plastic tarp when the container is not in use.
✔ If keeping the container long-term, install a metal canopy or simple lean-to roof.
10. Store Properly When Not in Use
Why? If you won’t be using your container for a while, it’s best to store it in a dry, shaded area.
How to store it:
✔ Keep it in a covered area if possible.
✔ Inspect and clean it before and after storage.
✔ Ensure it’s dry before sealing it up to avoid internal condensation.
Need a Rust-Free Shipping Container? Contact Container King!
A little maintenance goes a long way in protecting your shipping container. By keeping it dry, elevated, clean, and well-ventilated, you can extend its lifespan by years and avoid costly repairs.
Looking for a durable, high-quality shipping container? Whether you need one for storage, shipping, or a modified project, Container King has you covered. Contact us today for a free quote!
