It can be exciting to set off on the process of acquiring and reclaiming an industrial shipping container for personal use. But for all the fun and experience that comes from this endeavor, there is an equal number of challenges and questions to answer. Chief among those challenges just may be the question of painting a shipping container.
In this review, we’ll attempt to find straightforward solutions to many of your pressing questions about painting shipping containers. We’ll discuss the ins and outs of choosing materials, talk about some pros and cons, and tackle costs, time investment, and other issues.[toc]
Pros and Cons of Painting a Shipping Container
Ever since Starbucks unveiled a 100% storage container-based cafe in 2011, a global trend was kick-started for recycling shipping containers for domestic and commercial use.
But there are many questions that people reasonably have about painting these boxes. Why should you repaint them, or should you at all? Let’s take a look at the pros and cons.
- Adding paint will reduce corrosion and rust that appears when the bare steel is exposed to the elements
- To many, the sight of rusted steel containers conjures up an unwelcome or ugly appearance which painting can easily fix
- Painting recycled containers adds a personal touch that could improve home or business visibility.
- More control over the surface rust level if you invest in sand blasting before painting.
- The priming and repainting process can be costly, especially if you opt for long-lasting industrial-grade paints.
- Painting COR-TEN steel isn’t strictly necessary to increase lifespan
- Weathering the container steel (allowing it to rust naturally) can actually strengthen it in the long-run
How do you prepare a shipping container for painting?
The short answer to this question is: there are a few ways to do it. There are generally speaking two camps on this issue. Let’s look at both.
Some people choose to invest in sandblasting equipment to ensure the entire unit has an even, uncorroded surface. Sandblasting uses high-pressure air to expel particles at the surface, rendering it uniform.
The downside is, sandblasting will remove all the protective marine-grade layers that were already present. There is frequently a second layer of zinc coating on many containers which you’ll strip off with sandblasters.
Preparing the Surface Without Sand Blasting
The other opinion is to forego sandblasting-and the hefty bill that will follow from renting the tools-and begin priming after giving the surface a power wash. This procedure will keep the valuable marine paint and zinc undercoat. You’ll simply paint with your preferred color on top of it.
However you decide to remove the rust and dirt on the metal, the next step is to apply a primer in dry, cool conditions. We recommend starting in the mornings when the container is 100% dry.
Which kinds of paint do we recommend?
Before 2017, most trade-based industrial boxes were painted with solvent-based paint which was easy to apply but ultimately toxic and short-lived. Now, the overwhelming majority of storage containers are coated with direct-to-metal or DTM waterborne coatings.
Why the change in coating types? The answer has ramifications for your personal choice of materials.
Priming your shipping container
Don’t forget to prime your container box before painting! In our experience, you’ll achieve a smooth, even-toned coverage if you take the time to prime twice with an epoxy primer. Corroseal has primers that work well with the COR-TEN marine steel.
After priming, you can start deciding which type of paint suits you. DTM paint is water-based, widely available, and gives a durable sheen. We recommend acrylic alkyd enamel paint like those offered by Sherwin-Williams or enamel-based coatings from PaintMaster.
Of course, on top of the type of shipping container paint you use, you’ll have options for surface appearance. We recommend enamel paint because it gives off a professional opaque shine. But just like with priming, always invest in enough paint for two coats for optimal paint adhesion.
What about colors?
You could spend weeks and weeks deliberating over which color option will suit your container! Like the graffiti that often comes free when you purchase a storage container, the color option is limitless.
Overall, it’s a good idea to consider the environment and property in which the container will reside. Seeing a refurbished container in the world can be exciting for a retail customer and homeowners alike. We recommend neutral paint color on your unit if you’re looking for maximal appeal.
Lighter shades will tend to show rust on the exterior faster than darker hues. Make considerations for temperature too: darker paint jobs will lead to more heat exposure for people inside.
Container Paint Application and Removal
Whether you apply paint with a paint roller, paint sprayers, the most impactful thing to do is have good surface preparation. By eliminating the excess polyurethane paint, acrylic paint, and rust before adding a coat of paint yourself, you’re ensuring an even coat.
We recommend using a razor blade, pressure washer, or wire wheel to do detail work on rust or water damage.
Covering the Inner layer of Your Storage Container
While the outside of your container needs to show off a quality paint job with zero visible rust, the interior has its own quality.
If there is one requirement when coating the inside of your container, it is to limit VOC emissions as much as possible.
You can ensure that your inhabitants have exposure to minimal VOC levels by using a water-based coat. By investing in quality DTM paint, you’re doing a favor to life in the environment too. This paint releases fewer toxins which harm life less.
Covering the Exterior of a Shipping Container
DTM paint is also one of the best choices for exterior exposure. The color of water-based paint (even if you’re using a paint sprayer to craft a mural on the exterior) is richer and more durable than alkyd enamel and other industrial paint. We recommend using more than one coat to ensure less rust overall.
We also recommend you check out Por-15 container paint for a professional rust removal product that can be more efficient than using sanders or other hand use tools. Por 15 is a glossy black rust proof paint that seals rust away permanently from the container.
Insulating storage containers – paint options
Finally, there is also a special kind of paint that is effective as paint insulation. Ceramic shipping container paint is now widely available for moderating extreme temperatures in the container interior. Check out Super Therm for a storage solution that will reflect up to 95% of radiating heat that’s perfect for keeping your shipping container unit cool.
Cost – how much paint do I need?
Purchasing a storage container for personal use is one big project that can sap a lot of time and resources from your pocketbook if you’re not smart with the way you reason out your time. Luckily, we’ve found many answers to our customers’ questions.
On average, a 20 ft shipping container unit requires about 3-4 gallons of direct to metal paint. If your container has especially dark shipping line markings or business tags, you may use a third coat for a total of 5 gallons.
The cost of shipping container paint varies widely, so estimates for use are hard to make. Your time commitment will also change depending on a few factors. Is the corrosion process far gone on your container? Then you may need to pay attention to rust areas, stickers, and website information that need to be buffed out.
If your reason for purchasing a container is for domestic use, then you’ll have to spend a minimum of 1-2 weeks grinding and sanding the inside surface of your container to remove rust in the marine grade layers.
Overall, one person can prepare a shipping container in about a month. But every one works differently in different areas of refurbishing a container.
Now that we’ve covered the major points of discussion in the subject of shipping container paints, let’s look at some common questions.
Are shipping containers painted with lead paint?
The short answer is: sometimes. It’s important to do your research in the past shipping history of your unit. Check out this article from Discover Containers for more information. In short, make sure your unit doesn’t have phosphorous or chromate materials in the paint-then you’ll be OK.
Do shipping containers rust?
They do, but the steel they’re made of is specially made to get stronger with the presence of rust. A website called Shipped.com gives a clear-cut definition of why COR-TEN steel has properties that make it hard to damage with rust.
What is DTM paint?
DTM stands for direct-to-metal and it’s a special kind of coating that is ideal for spraying on COR-TEN steel. DTM is marine-grade steel, meaning it’s great for insulating its cargo (and for insulating domestic spaces.)
How much paint do I need to cover a shipping container?
Ideally, you’ll cover your container with 2-3 coats for a total of 20 liters for a traditional 20ft container. You can be more efficient by using a sprayer instead of a paintbrush, but both methods are fine.
The market for storage container renovation and painting has never been more vital. You can consult experts online or visit your local painting retailer and you’re likely to find solutions.
By investing time and energy in the recycling process, the container-living movement is gaining ground and converting people to a healthier environmental footprint. We hope our primer on how to paint a shipping container has helped you find a direction toward renovating your own container tomorrow!