With time shipping containers tend to get some surface rust that can turn into deep rust and can compromise your storage solution, even if you just bought it and it’s used, wind and water tight or cargo worthy, make sure you give them a coat of paint sooner or later just to protect it and extend it’s life. It might be a little bit time consuming but it’s not so expensive and that way you know for sure you’ve seen it all from the top to the bottom.

Used containers are a great option because they are the most cost effective and there is an abundant supply of these containers. A single shipping container has traveled throughout the world and has been exposed to the marine environment. When the container is moved, the areas where the steel panels are joined together become weakened under stress and the original paint can crack or chip away.

Because of being heavily used, water has an opportunity to collect in the corners or underneath the doors and remains stagnant. Painting the shipping containers makes the box more attractive in appearance and provides durability, ensuring the strength and integrity of the metal by keeping it free from rust.

Now is the time to paint your shipping container, assuming you are happy with the size, condition is strong and secure and the price was also the best on the market. Of course cosmetics will change and will look better and blend in with the surrounding area. Besides cosmetics there is another reason to paint your shipping container. Painting it, will add an extra coat between the steel and the elements, and will slow down the spread of rust and will make the unit last longer in any environment.

When your unit is damaged hard, in different ways, these scars can speed up the rotting process if you don’t take care of it right away. You have to understand that, the used units that are out there on the market, they are how they are, “as is”, “wind and water tight” or “cargo worthy”, they are kinda in the same boat. They all been decommissioned because they are no longer good to travel overseas, but this doesn’t mean they are not good for storage or different other building purposes, but they have to be maintained or worked on to be kept in a good shape. Don’t expect a used unit to be like new, or that you can immediately store goods in them, without doing a cleaning of the inside, sealing some pin holes with silicone or lubing the doors to work better. Otherwise you could just pay the extra buck and get the flawless one trip / new units out there and you don’t need to move a finger for them, since are coming in a very good condition almost flawless.

When thinking about rotting many customers are concerned with the chemicals used in making the flooring or paint. If you are going to use the unit for storage purpose, there is not much concern over the health risks. However it is not a bad idea to seal off the floor too, with a thick coat of paint, to prevent water damage and toxic fumes from creeping out. Any outdoor paint that is designed to be walked on and withstand the weather of all four seasons would work for the flooring, for example patio or porch paint can be the best choice.

Best option for painting the unit is a water based direct to metal ( DTM ) paint. Marine grade DTM paint. Rust-Oleum Marine Paint, Sherwin Williams and Vlaspar are making good marine grade DTM paint, or you can use any other marine grade paint at your convenience, brand is not a big deal as long you get the right product. Of course some brands may be of more quality than others, you cal also do a research online and find the best option for you and your budget.

On the rusted spots, use “rust converter” that transforms surface rust into hard substance and then your unit is ready to be painted. It also prevents the rust from spreading and secured the spot that is already rusted. There are some different brands and options out there, for example POR-15 rust treatment and prevention paint or you can do your research and you can choose from various brands options. But we’ve heard good things about this POR-15, that has high performance when it comes to rust-preventive coating, because it’s designed to be applied directly on the rusted surface. The POR-15 is ideal because it chemically bonds to the metal, and dries extremely hard, forming a rock hard coating, so it doesn’t chip, crack or peel like regular paint. It also keep moisture away which is getting stronger every time is exposed to moisture. This protective layer can be painted over with your choice of color.

What about the inside? Well everyone is asking about inside insulation, what is the best, if you think you want to do like a thicker insulation, you will then take some room from your inside space and so on. We’ve heard about ceramic paint insulation. Does it really work? You can try and see how it works. This type of paint it’s developed by NASA and the supplier claims it addressed all three modes of heat transfer – radiated, convected and conducted. EPA, the US Environmental Protection Agency suggests not to use paint as insulation but it is well recognized that it has the capability to reflect the heat off the roofs, so not to keep it cooler or insulated. So it;s your choice if you want to try the paint or just do an inside old fashion insulation for heat or cold.

We’re also talking about extending the life of your box. This can be done effortlessly and at an affordable cost. Because the unit is always sitting outside and it’s at the hand of the forces of nature, it can get a beating from sun, rain, snow and different temperature changes. It can start to rust and even the floor can start rotting inside. You have to take preventive actions to slow down the aging process of your unit.

PAINT YOUR UNIT – STEPS

The most effective way to clean up the rust to repaint a shipping container would be to power wash, sandblast the entire unit, remove the paint, then remove the rusted areas, prime and repaint the container. This would be a completely refurbished container. Sometimes doing this could be more pricey than the container itself, that’s why do your maths, see what is the better option, if you have time or the money to do it, or go with a new unit option.

If you want to cut some costs, you can just remove the rust and repaint the affected areas, get a wire brush, sandpaper, vinegar and DTM paint. A 20ft container needs around 3-4 gallons of paint. Try to remove as much or the rust as possible. Rub vinegar on those areas you cleaned and leave it to dry out. This will stall the corrosion process. Now it;s time to apply the DTM Paint, ideally , you should apply more than one coat up to 4-5 coats of paint.

Step 1 – Clean your container – Preferably with a pressure washer, remove dirt, debris and loose paint chips. Pay close attention to the areas that need special attention. Don’t forget to clean the top of your unit as well as the inside of it.

Step 2 – Grind down the rust – use the low grit sandpaper, steel wool or wire brush – sand all the areas to remove the corrosion or loose paint. If those areas are not well treated , they will compromise the coat of paint later on. Power wash the container again and rub with vinegar or any other rust removal on the areas that need attention. Let the unit completely dry.

Step 3 – Patch any holes or leaks – Sometimes you might find some pin holes around the unit, holes or leaks with silicone, industry approved fiberglass patches or welded. Cover the

Step 4 – Apply the “rust converter” – Apply over the rusty areas of the unit with a paint brush, roller, spray. A rust converter is similar to a steel primer and converts the rust in a hard, paintable surface. It also seals the rusted surface from oxygen, that way it is not exposed anymore. Let the unit dry completely.

Step 5 – Paint the shipping container – After the rust converter has dried, using a paint sprayer or a heavy paint roller is ideal when applying your paint, start painting the unit. Let the unit dry and enjoy your like new unit !

Make sure you lubricate the doors for a better experience when opening or closing the doors. You can find some helpful tips in one of our other articles here.

We hope that today you found out good information and tips in this article and it will help you with painting your unit.