In the past few years, the hype of the shipping container home concept has widely taken over the modular and tiny home industry worldwide claiming to be sustainable and cheaper alternatives.
Shipping container homes may seem like a ready box to live in, but they are not necessarily faster or better for living. In fact, it has various hidden underlying threats and issues that could create unhealthy living conditions. Moreover, there is almost no significant gain of time or money from the existing metal envelope.
It is clear from the table below that opting for a shipping container home might not save much cost or omit any of the steps of a basic construction.
A quick insight and comparison on the process of converting the shipping container into a home to that of building a conventional wooden home, can be seen below as well.
|Conventional home||Container home||Remark to Remember|
|Sandblasting, deep cleaning/ paint removal and repainting||Not needed||Essential||Due to the potential presence of toxic chemicals from previous transports or unhealthy chemicals in the existing paint|
|Foundation And Site preparation||Needed||Needed||A shipping container is heavy and steel, so a more expensive foundation with steel bolts, plates, etc. required.|
|Insulation||Moderate insulation is enough||Highest R-Value insulation needed||Metal being a good conductor, steel containers would require more expensive closed spray foam insulation- with the highest R-value.|
|Drywall||Needed||To conceal services and get a clean finish||It completely covers up the original wall, leaving no use for it.|
|Electrical||incorporated during construction||Need to create sleeves and walls to conceal the setup||Identical expenses|
|Plumbing||incorporated during the construction||Needs additional provisions for concealment.||Identical expenses|
|Roof||Needed||Additional secondary roof required for long term use.||To facilitate better drainage and avoid standing water, insects etc.For sound insulation.A secondary roof to withstand snow loads etc. and avoid sagging over time.|
|Structural members||Conventional engineering, structure from scratch||Based on the age of the container, design, size of openings etc., case-based additions.||The main load-bearing members are at the corners, so in case of large openings, combining two containers, or preventing the roof from sagging under snow loads, it might need added structural support.|
|Floor||Needed||Cover or replace the original floor for strength finish or hygiene||The existing floor is thin and unfinished and may make a lot of noise while walking.|
|Doors and windows||Needed||Needed||Extra time and energy to cut holes for openings.|
|Environment friendly||Employ renewable resources less carbon footprint||Employ nonrenewable resources, interrupting the original lifecycle, thus increasing the demand.||Shipping containers don’t end up in landfills at the end of their life but are recycled into usable metal scrap|
Details of listed disadvantages
The following listed reasons shall elaborate on every aspect of ‘why Shipping container homes are a bad option.’
Building permits for Shipping Container Homes
As shipping containers are not ideally built for living, obtaining building permits for a shipping container home can be difficult in many regions. Although many states in the United States (including Texas, California, Colorado, and Oregon) and countries like (China, New Zealand, and Costa Rica) host shipping container homes and have regulations in place, the particulars and standards are very tricky in most other places.
The code highly depends on the climate zones and regions, which calls for a very tiring research process and a lot of your precious time.
Bringing the container to your site
Transporting the shipping container to the site can be a tiresome and costly process due to these reasons:
- Weight: As the container are meant to withstand the harsh forces of water and storms in the sea and are built of metal, it is very inconveniently heavy. A typical 20 ft container weighs about 1.8-2.2 metric tons, and a 40 ft container is almost 3.8-4.2 tons. They need some specific and expensive equipment such as cranes and lifts to place it on and off the trailer and on the site without any damage, which is not ideally the case with small residential projects.
- Size: Ideally, these containers are designed to be transported from ports to ports or train stations or other transport services outside of the city. The city infrastructure often falls short to facilitate transportation of 20 ft or 40 ft long modules. Everything from finding the right trailer size to navigating it across the tight curves and turns within the city and then finally reaching and unloading on the site is tiresome. Moreover, these transportation services are heavily expensive. It is an important question to ask. Is it even worth investing so much more in transporting the container when you can build a similar house in place?
A potentially toxic environment
As the initial idea of using shipping containers stemmed from the need to repurpose them, so people intend to buy the used ones. However, it is vital to track what objects were transported in it. There is a good chance that it was used to transport toxic chemicals or pesticides, which could have spilt and absorbed on the floors of the container.
Even if deeply cleansed, the effect of these toxic chemicals is hard to get rid of and can cause harmful living conditions and life-threatening health issues. Pertaining to this, many customers eventually buy a new container, which defeats the major purpose of adapting the concept in the first place (repurposing) and pulls a container from its intended life cycle.
Although it is possible to track the information of transported goods from the ports, it is mostly only available up to the container’s last trip. So, people end up using a one-time used container to be safe, even though such container’s life and original purpose have not yet ended. It is crucial to realize that every time you pull one container out of the system, you create a demand for one new container. Hence more new metal, unnecessary use of resources, more carbon footprint in its manufacturing, and thus completely contradicting the sustainable and environment-friendly aspect of using the container for home.
The foremost and most evident concern with a shipping container home is heat insulation. A shipping container is nothing but a metal box with a steel structural frame. The walls of the container are heavy Corten steel corrugated sheets. As metal is a good conductor of heat, it needs heavy insulation to make it livable. Today, the best-suited insulation material in the market is closed cell spray foam, which has the highest R-value (a measure of insulation capacity) among its counterparts and is also the least thick, keeping in mind the limited space within the shipping container. But it is also the most expensive of all types.
The minimum R-value required for your home depends on the climate zone you are located in.
In some cases, a cheaper alternative, Insulation panels, are also used, but employing them in the interior could lead to a loss of at least 6-8 inches on either side out of the limited 8 feet interior width. Which further will have to be covered with drywall, leading to more loss of space, thus leaving you with a narrower room to live in. Moreover, you eventually end up doing all the steps you would do in a conventional home envelope, from insulation to building drywall.
Another concern with Insulating the interior is that it can cause problems with condensation due to significant differences in temperatures between the insulation and exterior metal wall. It could cause vapours to condense between the walls and insulation and lead to dangerous black mold within the space, making it unfit to live.
There is also a more recommended option of insulating the exterior of the container. However, it would only add to the expenses as the insulating material must be weatherproofed to sustain. Plus, it would lose the trending industrial look, which was probably a significant factor behind the decision to use it in the first place.
Even though a shipping container has a strong frame, it has relatively thin walls of corrugated steel. So along with heat insulation, it also needs sound insulation to become a peaceful abode. Otherwise, the rains will no longer calm you with the soothing drizzling sound, instead occupy you with the overwhelming banging noise on your ceiling.
You probably would have to add a secondary sloping or flat roof above your container to overcome the issue.
Restricted in Size
Shipping containers are available in two standard sizes. With a width of 8 feet, the height of 8 ½ feet and lengths available in 20 ft and 40 ft dimensions. It is a bare minimum for livable space. Even if someone manages to design within it, they have to consider at least 12-16 inches of space loss for insulation, wall panelling and drywall inside to conceal the electrical and plumbing lines and get a clean finish.
The option of combining two or more containers have also been explored in various projects to expand the widths of these homes. But it turns out it adds a more detailed complex engineering process: additional structural supports along the joint, sealing and roof slope adjustment, making it a rather expensive, tiring, and difficult process.
Based on the availability of these shipping containers and their transportation cost, you may end up paying more than required for owning a 320 sqft home.
Compromized Structural Strength
Shipping containers are structurally designed for stacking and transporting goods across the sea. It is composed of a structural steel frame and corrugated sheet walls. The corrugations in the sheet add to the container’s strength and make it fit to withstand inclement weather.
As shipping containers are not originally designed for living purposes, the following structural challenges are bound to occur in the long run.
- Sagged roof: The roof often sags with the weight of snow, as the prominent load-bearing members are at the corners. So container homes often need secondary rooves, load-bearing walls or structural members between them.
- Loss of strength due to openings: Cutting the corrugated walls for doors and window openings can compromise the strength of the container, indicating the need for additional structural bracing and reinforcement.
Even though containers are structurally sound, it is more likely that they need additional structural supports after the modifications for converting them into a home. Thus, the initial biggest pro of the container, its structural strength, does not hold up.
This is another reason that calls for a secondary roof to your container. The shipping container roof is corrugated steel and is very mildly convex, not enough to drain all the water. This can lead to standing water on top, causing insects, rust, mold, and a nasty smell, creating unhygienic living conditions.
Are shipping containers better for the environment?The answer is ‘NO’. It is a myth that Shipping containers end up in the landfill. In reality, most shipping containers are scrapped and recycled after their life ends and thus contribute to the existing metal demand and supply cycle. Therefore, there is a minimum need to repurpose them. Trying to do so only increases the demand for metal and thus the carbon footprint involved in the process.
A Reductive Process of construction
Whenever a shipping container is converted into a home, you have to eliminate some parts to open up the closed box for livable light and ventilation. It is an almost reductive process of construction, where you start by buying a whole box and then get rid of a significant part of the thing you bought to make room for more stuff that you need to invest more in. Why not start from zero in the first place?
Where could shipping containers still be preferred?
Even though they are not ideal for permanent livable homes, they could still be a feasible option, based on circumstances. Some of the reasons to still consider the idea of repurposing shipping containers could be:
- Temporary or relief shelters.
- For storage purposes.
- Easy or free access to a used container and professionals to work it.
- For the bold industrial aesthetic.
Like every project, these modular shipping container homes also require a thorough feasibility study. The availability, permits, transportation, worth, climatic concerns, health, and livability concerns, which are often more complex for shipping container homes than conventional homebuilding.
Even though it has gained popularity regarding its hurricane resistance and alleged sustainability, all the reasons and concerns listed above clearly highlight that they might not be the ideal solution for a permanent home.
Hopefully, this article helped convey all the hidden truths about shipping container homes and will help you make a more informed decision in your quest to own a home.
 https://www.youtube.com/watch?v=i7yEDz6bCfU- Belinda Carr