Six Mistakes To Avoid With A Shipping Container Home

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Updated On: December 29, 2020

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Table of Contents

This trend of constructing with shipping containers isn’t surprising considering that container homes are Eco-friendly, affordable, and incredibly strong.

When you look at examples of shipping container homes, you find homes that were built extremely fast and for a small amount of money.

However, there are also examples of container homes that have failed because their owners have made simple mistakes that could have been avoided.

Here are a few common mistakes you can make when constructing a shipping container home.

Using the Wrong Size Shipping Container

The biggest mistake people make when building their shipping container home is purchasing the wrong size shipping container. In fact, this was the most common response we received when interviewing dozens of shipping container homeowners.

Most of the people constructed their building using regular height shipping containers, only to find out later that there are high cube containers which are an additional foot in height.

Example Of High Cube Container

High Cube Container Height Difference

Standard shipping containers are 8 feet 6 inches in height, whereas high cube containers are 9 feet 6 inches tall. An extra foot in the height of your container is perfect for people looking to insulate the ceiling of their container without sacrificing on headroom.

In a standard container, if you insulate the ceiling, the remaining interior ceiling height is only about 7 feet. Using a high cube container, you can install insulation and still have an 8-foot ceiling height.

High cube containers do cost a bit more, but they are quite popular and not too difficult to find. Considering the benefits they offer, it’s usually money well-spent.

Other people are surprised to find out that containers come in lengths other than just 20 and 40ft, including, 10, 45, and 48 ft lengths. There are even some containers that are a few inches wider than most, including 53 ft containers and so-called ‘pallet-wide’ containers.

Check out our Shipping Container Dimensions article to learn about the sizes, weights, and more for all the common (and not so common) container varieties.

Buying Containers with the Wrong Condition

Another crucial mistake people make is not accounting for the condition of the containers they purchase. While purchasing used containers is a great way to increase the sustainability of your home, you need to be prepared to do some refurbishing.

At the low end, you’ll often need to some do touch up painting. But more heavily used containers may require cutting out dented or rusted metal and welding in a patch. Containers naturally experience significant rust and corrosion due to their hard lives at sea and in busy ports, and it must be dealt with.

If you’re prepared for this work going in, that’s one thing. But people purchasing their containers online or by telephone without seeing the containers in person may be surprised at the condition of the containers when they arrive.

Even if you have pictures beforehand, a shady dealer could conveniently crop out bad places from the pictures, or make them hard to spot with lower quality images. Seeing the containers in person is preferable, but at least get numerous high-quality images and videos if you can’t physically be there. Ensure all the corner joints are shown, and underneath and above the container is ideal if possible.

Old Rusty Shipping Containers

We have a ton of great information about choosing the best containers for your project, how and where to buy containers, and also how to handle container delivery that is sure to help you avoid any surprises.

Not Understanding Local Planning Regulations and Building Codes

Just about the worst feeling in the world is when you’re told that your already built house doesn’t comply with local planning regulations and that you need to take the house down. You don’t want to end up like this person, who had to take down their $1.5 million home because they didn’t apply for a permit. And even if things don’t get THAT far, you can still face significant delays and cost impacts from regulatory hurdles you didn’t expect.

Always contact your local public works building division, zoning office, and other applicable officials as early as possible in your project before you start construction. Be prepared by having a very good idea of what it is you want to build and where you want to build.

Not Researching Local Planning Regulations

This normally means having scaled architectural drawings and foundation plans drawn up before you meet your local planning department. The planning application can take anywhere from a few weeks to a few months and can cost hundreds or potentially even thousands of dollars depending on local fees and other required assessments.

Unfortunately, each area has its own rules and standards, so there is no one standard approach that fits all situations. Note that in the US, there are some areas that fall outside of city zoning. In these areas, a permit is not needed for building. If you are in such an area, consider yourself very lucky! But in most cases in the US you will need permits. Make sure you do your research first.

Luckily, we have a detailed article about zoning and building regulations to help you navigate these issues!

Using the Wrong Type of Insulation

A mistake people make with insulation is not considering their local climate. For instance, in areas with lots of rain, you need to ensure your insulation provides you with a seamless vapor barrier. The best option would be to use spray foam insulation.

Shipping Container Home- Spray Foam Insulation

Courtesy of Larry Wade

In very warm, dry climates your insulation should focus on keeping your container home cool. Generally, in this case, you wouldn’t want a seamless vapor barrier.

There is no one correct approach when it comes to insulation. It depends on many things like the local climate, your budget, the container’s age, and the style of home you want.

Most people agree that spray foam insulation is the best to use in most circumstances. It certainly isn’t the best choice for every situation. There are many other types of insulation such as insulation panels, blanket insulation, and even Eco-friendly insulation such as recycled newspapers.

Choosing the correct type of insulation to use is crucial. If you are using the wrong type of insulation, or worse yet, don’t have any insulation, you are going to face lots of problems. Your container home will be freezing in winter and too hot during summer. However, your biggest concern is condensation and dampness.

Condensation can cause your containers to rust. This is very expensive to repair and can take a lot of time.

If you aren’t familiar with insulation methods and techniques, read our beginner’s guide to insulating a shipping container home.

Cutting Too Much Steel Out Of Containers

Additionally, a common mistake people make is cutting too much steel from their shipping containers.

A key feature of shipping containers is that they are incredibly strong. In fact, they can be stacked up to eight containers high when they are fully loaded! Shipping containers are the perfect building block to use for fast, affordable construction.

Unfortunately, some people over-modify their containers. By cutting out large sections of steel from the container you are reducing its strength and thus the structural integrity of the container. Doing this will also require you to incur additional costs, because you will need to reinforce the containers with steel beams. You will also need to weld the steel beams in place, which can further add to your costs and includes time-consuming preparatory work.

You can remove sections of steel for your windows and doors without much problem, but when you remove entire walls, you will need to use support beams.

Choosing the Wrong Builder or Contractor

The last mistake we are going to look at is people choosing the wrong contractor to construct their shipping container home.

Many people like to build their shipping container home themselves. People without the time or DIY experience will need to hire a contractor to construct the building.

When you choose a contractor, make sure that they have experience building with shipping containers, or, at the very least understand shipping container homes and are enthusiastic to construct one.

The last thing you want is a builder who doesn’t understand shipping containers. This will cost you time, money and certainly won’t be exceptional quality.

Also, make sure you choose a contractor who is able to follow the build all the way through the project. You don’t want to use multiple contractors during the build, if possible.

Let us know in the comments section below any mistakes you made while constructing your shipping container home.

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Check out more great articles:

How to Cut Openings in Your Containers

Almost every container project design is going to require cutting a container in some form or fashion. Whether you’re adding windows, doors, or just expanding

69 Responses

  1. What if I’m converting a container to a home but I think I will have to move it at some point after its a home. Do I need to frame it differently or are there other concerns I need to know about it to make it okay to pick it up and move it? Thanks

    1. No real changes required to the interior wall framing specifically. When you pick up a container, it can flex a little bit. In theory, this could lead to cracking of brittle materials such as tile grout or drywall. If you’re planning frequent moves, being thoughtful about choosing materials that aren’t especially brittle may be wise. Providing good structural reinforcement around windows and doors will help ensure you aren’t losing any strength from these openings. And a careful crane operator (or whatever piece of equipment used to move the container) with a steady hand will help as well.

  2. I am new to all of this but I have been doing my research. I plan to build two to three separate shipping container homes on the same property (one or two of them to be 2 stories). I hear things like ‘Insulate the outside of the shipping container to protect the rusting’ if there is extreme heat on the outside and extreme cold. Now in Texas, the heat can get intense so I try to always keep a set temp between 67-70 degrees inside. What is your advice on insulating the outside of the shipping container to protect against rusting and condensation with cool temperatures on the inside and extreme heat and humidity on the outside?

    1. For most people, the choice to insulate on the inside vs outside of the container comes down to aesthetic preference. If you want your home to look like a container from the exterior, insulating on the outside is going to be a problem because everything will be covered up with insulation and cladding. However, from a technical standpoint, insulating on the outside is arguably superior. It will give you more interior space and keep the highly conductive metal away from the outside temperatures.

      To better understand how insulation, condensation, and heat work together, we suggest reading these three articles:
      https://www.discovercontainers.com/essential-knowledge-about-heat-transfer-in-shipping-container-buildings/
      https://www.discovercontainers.com/container-condensation-prevention/
      https://www.discovercontainers.com/5-methods-to-insulate-your-shipping-container-home/

  3. I am trying to build a cabin in mountains and my house site is sloped.. I want to put two 30 ft containers on the lower side of the hill and bridge two 40 ft containers from the top of the hill . 8ft ends resting on the bottom 30’s . Is it possible to separte the upper 40’s 14 ft apart to make the upper portion 30×40? I would then like to bridge the four with a metal atic truss roof. And of course put flooring between , Is this possible?

    1. Yes, this is certainly possible. Bridging the space between two parallel containers is a fairly common design idea. You can find prebuilt roof trusses that will handle this span pretty easily. For the floor, you’ll need a good floor joist that can handle the 14-foot span, with an understanding of your design and usage to know about expected floor loadings in this area. This will determine things like material type & size, spacing, and if you’ll need additional foundation elements in this area or if you can just tie into the bottom rails on each of the parallel containers.

  4. Aren’t shipping containers made from Corten Steel? which eliminates problems with rust, as it’s produced specifically that the rust layer actually creates a barrier to stop the material rusting further, commonly used in architectural steel work and sculpture?

    1. Yes, they are made from Cor-Ten (or weathering) steel. However, this steel is only intended to slow the rusting process, not completely prevent it, by forming an intentional, protective layer on the surface. Factors like the presence of paint, pooled water, proximity to saltwater, localized air pollution, etc. can lead to ongoing corrosion issues. Long story short, without proper attention, care, and maintenance, shipping containers absolutely can rust.

  5. We are hoping to use shipping containers as a retaining wall/garage shop area. Would the container be able to use one side for retaining a wall? We plan to have a rock barrier for drainage. Worry about longevity.

    1. Garage/Shop area is fine, and we have a great article about exactly that: https://www.discovercontainers.com/shipping-container-garages/

      However, we don’t recommend using the container as a retaining wall. To some degree, this depends on the topology of your yard, but in general, it’s not a good idea. Containers are their strongest supporting vertical loads on the floor. The sides are quite strong as well, but they aren’t really designed to support continuous horizontal loads like that and it’s difficult to quantify exactly how much they can safely hold for a loading that isn’t in line with their original intent. More importantly, using a container as a retaining wall, even with a rock barrier, is going to be a hotspot for corrosion. Water, air, and minerals from the soil are a tough environment, and you can’t inspect the container’s condition when it is covered. You’d be in a slightly better position if you used a high-quality corrosion-inhibiting coating, but even then we’d recommend you use something non-metallic for the retaining wall instead of a container.

  6. If I only have 15-16″ of space and not 20″ for the container, can I cut it to fit the space and add a window where it was cut?

  7. my house is a double-wide trailer stacked on top of 4 tightly placed 20′ shipping containers, all sided into one building. there are 6×6 beams running across the shipping containers that support the upper level that stick out to create a wraparound deck. which was already approved and insurable by local authorities.

    I’m hoping to turn two of the shipping containers into bedrooms by adding windows etc. but was wondering about the structural integrity if I took about 10′ of wall out of the one end of the 2 containers to make a larger 16’x10′ foot room.

    From an engineering standpoint, do you think would still be safe and insurable?

    1. That’s something you’d need an engineer to run some calculations on based on the type of beams, weight of your house, wind loading, foundation type, etc. If the entire load of the trailer is carried by the 6×6 beams, which in turn directly transfer that load into the corner columns of the containers, then the container walls should be unloaded and cutting windows in them shouldn’t be a factor. But hard to say for sure without a detailed understanding and analysis of the situation by a local engineer.

  8. Hello, My question is if I stack one container on top of another can i use the top container floor beam as the Header by welding the top of the lower container to it and taking the wall out completely bellow it?

    1. When stacked, the top and bottom containers should only actually touch at the corners. You’d need some thin spacers (1/4 inch thick or so) to fill in the gap. Then, you could weld the bottom side rail of the top container to the top side rail of the bottom container. Subsequently removing the sidewall from the bottom container will reduce its strength, but for most light residential use, you’d probably be WELL under maximum loading anyway. If you have some especially strenuous/heavy usage planned, then you should work with an engineer to ensure everything is safe.

  9. Thank you, your site is a great ressource!

    Question: Is it possible to simply take out the steel door of a container permanently (i.e. for joining containers together, or for installing a large glass front), or would the container still need reinforcement?
    Side door containers already come with a reinforced structure, correct? So can I just take out the steel door and put a glass front in their place?

    1. The two main steel doors on a container, when closed and latched shut, add to the structural integrity of the container (this is discussed in the ISO standards). However, using a container as a house is *usually* (depending on your design) much less stressful than being fully loaded with cargo, so you have enough factor of safety to accept this slight reduction in strength without issue. The same applies to containers with side doors. Now, if you’re planning on stacking containers, putting extremely heavy stuff inside, etc. then you may need additional structural reinforcement if you want to permanently remove the doors.

  10. I’m looking at using a high cube containers three right next to each other as a basement of my house. would they be able to support the houses weight. with a foundation laid on top.

    1. The four corners of each container are quite strong and should be able to support most reasonable houses if the forces are directed into those corner columns. Of course, you’d need suitable footings under the containers to transfer the load to the soil and prevent settling. Keep in mind that containers don’t have an especially strong resistance to the horizontal forces from the soil, so you’d need additional structural reinforcement to account for that.

  11. Hi

    I have a 40′ High Cube reefer, and a 20′ standard reefer that I want to join together to form an ‘L’ shaped space.

    I plan to cut an 7.5′ wide opening in the side of the 40’HC, and remove the doors from the 20′ unit and abut them together, keeping the floors at the same level.

    I plan cutting the 40’HC just far enough away from the corner, so as not to compromise the structural integrity of the unit.

    I would like to be able to separate the containers at some later stage.

    My question: Is there a kit to facilitate such a junction? and if not, what’s the best way to achieve a watertight seal.

    Regards
    Conor

    1. To our knowledge, no such kit exists. Typically, containers that are attached in this way are done so permanently with welding (or less commonly, epoxy). Given that you want to be able to separate them at a later date fairly easily complicates matters. The first step would be ensuring they are both on stable foundations so that they won’t move and caused problems where you join them. You could use the corner fittings on the shorter container as attachment points, but for the longer container, you could consider welding a bracket of some sort onto the top and bottom beams on the side where the attachment will be. This will give you something to attach the shorter container to with a bolted connection or ‘bridge connector’. You’d also want to use some type of plastic or rubber material along with caulking to seal around the edge where the two join and keep the elements out.

  12. Excellent read, I just passed this onto a friend who was doing a little research on that. And he actually bought me lunch since I found it for him smile So let me rephrase that: Thanks for lunch!

  13. Is there any reason one cannot use a 6×6 treated board for the support? It is less expensive and does not have to be welded. They can hold 12k pounds of weight each.

    1. Kelcie, you need to be very careful saying things like “they can hold 12k pounds of weight each”. A few things to understand:

      -Unlike steel, wood is not uniform. There are variations in species/type of wood and grade (which reflects the grain shape and orientation, straightness, knotting/pitting, etc.).
      -Dead and live loads (or static and dynamic loads) affect materials differently. Think of the difference between your container just holding stationary boxes vs having a weightlifting or jump roping class inside.
      -The direction and type of loading greatly affects strength. Contextually it sounds like you’re talking about axial column loading (and not use as a beam, which causes both shear and bending moment stresses), but it’s important to be specific. If as a column, how long is the column, as at a certain length, you have to start taking buckling/bending into account. Also, if as a column, you have to factor in not just the vertical load, but horizontal loads like from wind hitting the container, etc.
      -It’s unclear if you’re talking about loading to breaking strength or loading to a calculated working limit or with a factor of safety applied. And if there’s a FOS, what is it and how was it calculated/what is it based on?

      As you can see, this is all pretty complicated. A lot of this is covered in tables for structural wood that engineers and building contractors use.

      With all of that said, could a relatively short piece of 6″x6″ (nominal) lumber be used as a vertical column and hold 12k lbs of force safely? Probably, as that seems within the realm of what’s reasonable, but you’d really need to know more about the wood and the loading of the container then consult a table to be sure.

      You also have to think about the attachment of wood to the container. Metal can be welded, forming a rigid connection. Wood cannot really be rigidly attached, and thus forms kind of a hinge at the attachment point. This usually has to be overcome with diagonal bracing, etc.

    1. Unfortunately, we aren’t able to keep track of the regulations for every city and county. We will say that it’s VERY rare for a container house to not be allowed, just because it’s a container house. However, you might find that you are required to have a home of a certain size or appearance via exterior cladding, as well as compliance with local building codes. These requirements apply regardless of the type of construction used.

  14. Miami has a few restaurants and businesses that are operating out of that location you can Google it and find it. And I believe there’s one private home in Englewood Florida just Google do-it-yourself container home in Englewood and you’ll find it.

  15. Thoroughly enjoyed this article’s approach to a shipping container home. If only there was a book/article for every area outlining rules and regulation…

    1. At least in the United States, regulations pertaining to a building are mainly made at the city level, so it would but quite an undertaking to compile, and would immediately be out of date. The majority of regulatory hurdles you’ll face will be building code related, and cities don’t typically create their own building codes but incorporate different versions of the international building code (IBC) and international residential code (IRC). However, there are some zoning type rules that are city-specific, and also some states have regulations around things like wind and earthquake resistance, for instance. Long story short, the best source is just speaking with your local government office that handles these things.

    1. Send us an email via the ‘contact us’ page at the top and we can discuss this more in depth.

  16. Hi,
    I have recently looked in to the different types of containers there are and have found ones that do not have rooves and are open for top-loading. This leads me to a question of stacking, namely is it safe to stack a container on top of an open top container then cut half of the floor out of the top container creating sort of a loft.

    1. Open-top containers can be stacked without issue. The roof of a traditional container has minimal structural load. As far as stacking to create a loft, what you’ve proposed doesn’t seem to have any high-level issues.

  17. I’m asking this for my HSC Major work, is it possible to stack joined shiping containers with the side removed.
    I need to know this ASAP as my school does compressed unit HSC and I only have 6 weeks out of the 10 weeks given to complete the task.

    1. It’s certainly possible, but how advisable it is depends on a number of factors, most importantly, how much load will be placed in the containers. The corrugated sides of the container do have a structural load on them from the floor. The sides transfer some of that load into the two horizontal beams in the ceiling, so removing a side removes some of that capacity. In order to answer this properly, you’d really need an engineer to do a finite element analysis on the modified containers with the expected loading added.

  18. Hi,

    We live by the beach and have regular typhoons. What are things to look out for and are container vans even an option for us?

    1. They are certainly an option for you still. Remember, containers are used on ships where they are exposed to high winds and salt spray daily. The three major things to keep in mind are: (1) ensuring the container is rust proofed and coated so there is no bare metal. This is obviously more of a concern for used containers than new ones (2) ensuring the container is adequately attached to the ground. Containers are very heavy, but they can move with flooding and high winds. The corner attachment points need to be anchored to the foundation securely (3) every penetration made in the container for windows and doors weakens the structure and provides a less durable surface for flying debris in the case of a severe storm. Consider having metal storm doors that cover the windows and doors, and additional structural members to account for material that is removed for penetrations.

  19. Hi, I just read the questions and I wondered about the one that Bruce Anderson asked about laying the container on it’s side to get a 9’6″ floor. I am guessing that the normal floor of the container is somehow different than the walls, besides just that they seem to have a wood floor on top of the shell. Does any one know how the floor is different so maybe the wall could be beefed up to become the floor. I love the idea of having an extra 1.5 feet in width. thx, Neddy

    1. That’s a bad idea. Shipping containers are designed for vertical loading. Turning them 90 degrees on their side completely changes how the structure is loaded. Additionally, the wall and floor are completely different: the wall is just a single piece of corrugated sheet metal, unable to support anything close to the load of a floor. The plywood floor you see has substantial structural members underneath it (just look on the underside of a container to see).

  20. Aloha,
    Living in the wettest side of Big Island, HI
    After reading this article foam insulation seems the best bet for mold/condensation?

    1. Aloha! Yes, closed cell foam insulation is usually the best bet. It can contour to the corrugated steel walls preventing air gaps, and it’s fairly impermeable and thus will not become saturated with moisture. It also has just about the highest R-value per inch.

  21. Whats the maximum number of containers that can be stacked vertically, without compromising the stability of the overall structure?/

    1. The highest container stack you typically see in port situations is nine containers, although this is with ‘static loads’. When human occupants are involved, this becomes ‘dynamic loading’ as the forces on the container change as you move yourself and furniture around the containers. We’ve never seen a house with anywhere near nine containers stacked on each other though. If you look closely, most large stacks for human occupancy have a separate steel structure that supports the containers, instead of simply stacking them. In short, for any complicated stacking, we recommend speaking with a structural engineer to ensure the project is safe.

  22. I am trying to start a shipping container home I have no idea on how to cut them out I was gonna take the whole wall out the middle glad I came across this site how do I join them together and how should I cut it out I want the two end rooms to go across both container how is this done

    1. Loycee, the most common ways to cut the walls out of a shipping container are as follows, in order of speed: plasma cutter, acetylene torch, abrasive cut-off wheel in a grinder. Joining the containers together requires welding some addition metal in the gap around the periphery of your cut. Be sure to seal the new opening well to prevent moisture intrusion and air leakage. Most important is adding structural reinforcement to offset the removed metal. This depends a lot on the design of your particular home, so it’s best to ask a structural engineer for specifics on this reinforcement.

  23. Hi
    Can I remove the gable ends of a shipping container . One end will be for a fixed window . The other end will. E for a window and door . Will I need to structurally stiffen the steel frame of the container if I do this ?
    Scott

    1. Hi Scott,

      We have seen this done before and yes the ends needed to be reinforced. We can’t advise you on the specifics though as we’re not entirely sure what you have in mind.

  24. Hi,
    I came to your blog when searching for an answer to my question – has anyone experience of turing a highcube container on it’s side? I am attracted to getting a 9’6″ wide floor, and appreciate it will lower the ceiling height, but can live with that, if the structure can stand it.

  25. I am in the process of joining two 40′ shipping containers. I am cutting out 20′ in the middle to have a large 20’x16′ center room and 4 smaller 10’x8′ rooms. I am considering an exterior spray on foam insulation with an elastomastic artic white coating. (New Mexico) any recommendations on the insulation?

  26. Do I need to insulated the ceiling as well as the walls? I live in oklahoma. Thank you in advance.

    1. Hi Elaine,

      There are no yes/no answers. It really depends on the R-value you’re looking to reach.

      With that being said, generally, we recommend that people insulate their ceilings…

  27. Hello, if I wanted to link 2 containers (one is 40×8 foot, and the other is 20×8 foot), in a way that the a long elevation of the second container is is completely open, will it affect ob the strength of the containers? Thank you.

    1. Hi Rita,

      Yes it will impact on the structural integrity of the containers. You will need to reinforce the opening if you’re planning to remove the entire side wall.

  28. We’d like to have two 40-foot containers on the first floor and two of the same perpendicular on the second floor. (creating a courtyard/atrium of sorts. How wide apart can the containers be placed apart/span with and without a support column. Can we create a full 24×24 courtyard or will it need to be smaller or have a lot in the way of support columns to support a glazed roof over the whole thing? Thank you.

    1. Hi Rachael,
      It would be in your best interest to get an engineer to draw up plans on any structure that will be more than one floor, also if it is going to support any type of other structure on top of it.

    1. Hi Bill,

      A 20ft high cube container unloaded will weigh around 2,350kg.

  29. Hi Tom, I just joined minutes ago. I want to erect a 4-5 family building on what now is occupied by a 3 family home with ample room in both front and back yards. I am reading everything and know that I first must contact my local zoning board for clarification as to what they will and won’t allow. Thank you for be an enthusiast. I am going to need one. Talk to you soon. Dianne

    1. Hi Dianne,

      Thank you for deciding to join us.

      Please keep in touch and be sure to email us if you have any questions.

  30. What about to remove the complete ceiling to add a second container and then get a living room double height?

    1. Hi Silvia,

      Yes you could do this. In addition to removing the ceiling of the bottom container, you’d have to remove the floor joists and plywood of the upper container.

  31. There is no single or simple answer to that question as it is too generic. There is no safe amount it depends on where you are taking it out. Let’s say you cut a square foot out of a corner, that could be really really bad. Whereas cutting a square foot from a side could be done and have no problem. It really needs to be evaluated against what it is you are trying to accomplish. A door and window, for example, have it’s own framing to support it and can be done relatively safely. But again it depends on where they are taken from leaving us with the only safe answer not having enough detail as – there is no amount of steel that can be safely removed without the specifics.

  32. Hi.
    Does anyone know what is the maximum amount of steel that can be removed from a shipping container without compromising its structure?