You see everywhere shipping containers homes and they are growing in popularity so you probably thought about getting one and turn it in to your comfy home already.

Or if you already have one and thinking of turning into a livable space, for sure insulation is an important step in building your dream home out of the shipping container. The units are cheap to get, even a new unit is cheap comparing with getting a regular traditional home. Building your house will be also faster, cheaper and eco-friendly, due to the less energy used to make them and also by recycling the shipping container using it for a different purpose than he was built to.

Insulating the shipping container – takes a little bit of time if you want to do it yourself and might be less time consuming if you hire a contractor, either way most of the people are handy enough if you have a few tools and want to live off the grid, you can turn these homes in an affordable way, by using eco-friendly materials and in the end will reduce dependence and lower your utility bills.

When insulating a shipping container, you’re separating the conditioned airspace from the outdoors. It’s the same thing you’d normally do with almost all enclosed structures that have climate control ( A/C or heater ). Shipping containers need insulation to make them livable. They bake in hot climates and freeze in cool climates because heat moves easily through steel.

What climate are you setting the container in?

All your insulation decisions begin with the climate. Insulation keeps the outside weather outside and the inside temperature inside. The more extreme temperatures you face, the more insulation you need. If you’re building in a temperate climate, you may emphasize weatherproofing over insulation. One note of caution: If you don’t insulate your container, not only will your home be harder to heat and cool, it may also be susceptible to moisture from condensation, which can lead to an assortment of problems like corrosion and mold.

People build shipping container homes in the Arctic and the tropics. Each climate requires varied materials, designs, and applications. Before you make any decisions about insulation, understand what you want it to do. With that said, some people still need heating and air conditioning in these climates…and thus should strongly consider insulation. Whether you will need climate control for your shipping container home or not depends on your personal preferences for what is ‘comfortable. With additions of fans in warm climates and warm clothes in colder ones, you may be able to endure the normal temperatures without any added insulating material.

A few factors to consider when evaluating your options to insulate your shipping container.

Air Leakage: How well the insulation prevents air from flowing through it and around its edges

Net Interior Space: Directly correlated with R-value, this is how much space is left-over in the interior of your container after accounting for necessary insulation and interior wall surfaces

R-value: How well the material prevents transmission of heat energy

Performance: Performance characteristics are affected by things like material, entrapped gas, open vs closed cell structure, etc.

Vapor Permeability: How well the insulation prevents vapor from migrating through it and staying in it

Eco-friendliness: Many people are attracted to shipping container homes because they want to build and live in a sustainable, environmentally friendly manner. These materials vary quite a bit in the ecological impacts of their manufacture and installation. Vapor Permeability: How well the insulation prevents vapor from migrating through it and staying in it

Cost: Factor in both material costs and labor/equipment costs depending on if you’re doing it yourself or hiring a contractor. Remember if you’re doing it yourself, ease of installation is worth considering.

Will you do it yourself or get a contractor to do it for you?

The shipping container homes are popular among DIY enthusiasts because shipping containers can reduce the need for skilled labor. Before you design your home, decide how much work you want to do yourself. A DIY home can cost less money but you get the pride of making your own shipping container home. Keep in mind that your building options may be limited by your skills and budget.

Think about it, that contractors make construction move much faster. If you decide you want to DIY talk to some experienced workers, learn some skills throughout the construction process, go and search some online videos. Contractors, though more expensive, already come with the skills and tools they need.

What options you have to insulate the shipping container?

Keep in mind that shipping container construction works differently than traditional home construction, because of how steel boxes function in humid environments. The interior of a shipping container “sweats,” or there will be some condensation for sure. Water causes steel to rust, and your home will deteriorate much faster. It also can destroy any internal construction material like wood or drywall.

Blanket Insulation

Coming in the form of “tiles” (pre-cut lengths to fit typical wall heights) and rolls (long rolled-up pieces that must be cut to length during installation), blanket insulation is somewhat “fluffy”, compressible, and not self-supporting. It’s much like the blanket you might use to keep warm in your house on a winter evening, except thicker and made of different materials. In almost all cases, blanket insulation makes use of long fibers mashed into a small space, effectively making it open-celled. Blanket insulation is intended to be fastened in the cavities between studs and uses those studs for structural rigidity since it will just fall over into a pile without support. It is one of the cheapest options and is very easy to install, typically only requiring a stapler to fasten to studs.

Some options for blanket insulation are: Fiberglass, Rock/Mineral, Slag Wool, Sheep Wool and Cotton rolls.

Blanket insulation is quite permeable to water vapor, which in traditional construction can be mitigated with a vapor retarder. However, as we discussed in our condensation article, vapor retarders are usually not good choices for container homes because the outer metal skin is already a vapor barrier itself, and you can end up trapping water vapor in wall cavities. Some of the fibers used to make blanket insulation, most noticeably fiberglass, can be irritating to eyes, skin, and respiratory systems. Proper PPE (personal protective equipment) such as a dust mask, gloves, and safety glasses is necessary before handling these materials. Consult the MSDS (Material Safety Data Sheet) or other instructions on the product packaging for proper handling procedures.

Expanded Foam Insulation

Expanded foam is manufactured offsite into large boards and panels that are pre-sized for typical wall heights. Unlike blanket insulation, it is self-supporting. Holes for things like doors and windows are made on-site by cutting. The gas in closed-cell variants can sometimes escape the cells and cause a reduced R-value over time. It is DIY-friendly and can be attached to studs or even glued right to the container. It can be pretty quick to install unless you have a lot of cuts to make. Some varieties are molded to match the corrugations of a shipping container wall. If not, you’ll have large air gaps in these corrugated areas.

Materials for foam insulation could be but not limited to : Open Cell Polyurethane Foam (oc PU Foam), Closed-Cell Polyurethane Foam (cc PU Foam), Extruded Polystyrene Foam (EPS), Expanded Polystyrene Foam (XPS) or Polyisocyanurate (Polyiso)

Spray Insulation

Spray insulation can be made out of several materials that are all applied by spraying or pumping out a liquid mixture that then hardens into a solid. Due to how it is applied and adheres to itself, spray insulation is continuous and expands into nooks, crannies, and cracks. This forms a barrier that resists air movement as well as the transference of heat. One time of spray insulation expands upon application then hardens, which helps further with sealing. However, it does require trimming as the expansion will push the foam past the face of your studs.

Options for spray insulation could be : Open-Cell Spray Polyurethane Foam (ocSPF) – less used, Closed-Cell Spray Polyurethane Foam (ccSPF) – most common and recommended, Damp-Spray Cellulose – other option, Cementitious Foam – eco-friendly but not that good in R-value and can be crumbly.

Not the old fashion traditional insulation

This category of insulation is made up of materials that somewhat unconventional, often are chosen at least in part for their eco-friendliness, and are usually consider cheap insulation. Their performance makes them less suitable for most owners given their low R-value per inch unless the eco-friendliness is your highest consideration and you’re willing to sacrifice interior room for it.

Straw Bale: Much like the straw bale you might use to feed a horse, but instead stacked like blocks. Due to the size of straw bales, this would only work for insulation on the exterior of the container

Hempcrete: A material similar to concrete but with less strength, and made out of hemp.

As you can see, the options available are quite extensive. Choosing the best insulation for you really requires a proper understanding of your own decision making factors, like budget, climate, design, and personal tolerance to hot and cold. If you ever are in doubt, take a look at what people around you and in your geographic area are already doing. It’s often easier and cheaper to use materials that are already common for your region. A conversation with a local construction contractor to get site-specific recommendations and advice may also be useful.

Heating and cooling

Heating and cooling both have different solutions beyond insulation. In the summer sun, a shipping container acts like a greenhouse. To keep the sun from affecting internal temperatures requires significant insulation unless you use a radiant barrier—material that reflects the heat. Homeowners often use special paints or reflective materials on the exterior of their shipping container. A rooftop garden, or living roof, also keeps out radiant heat in the summer, and it is beautiful, too.

A green or living roof is a garden of sorts on your roof, with various grasses and other plants. Soil and plants aren’t great insulators, but they can help to block solar radiation if you live in a warm climate. A green roof, therefore, isn’t really a replacement for insulation, but a supplement to it. An additional benefit of green roofs is that they look cool! From the sky, your container will look like just another patch of ground. And while it’s not a great option for insulation it’s still an environmentally conscious choice and does add an element of protection.

In a primarily cold climate, you want two things: draw in the sun’s radiant heat and prevent heat from leaving the home. Find a place with plenty of light and line the exterior of your home with material that is not reflective. Heat loss happens primarily in two places: your roof and your windows. One pane of glass can lose as much as ten times the heat as an insulated wall. The more window space you have, the more you will need to insulate your walls.

While the other types of insulation mentioned above work to slow the transmission of heat energy via conduction you still have radiation to think about. Radiation is the least understood form of heat transfer, but it’s incredibly important in shipping container construction. Unless you’re open to draping your container with a space blanket likes the ones commonly carried by hikers, getting a radiant barrier is likely going to involve a coating of some sort. Be careful to notice the difference between paint and coatings that are specifically designed to reflect and emit radiation energy. Coatings are specifically designed to reflect the invisible infrared light of thermal energy, and though they may look similar to paint, they work much differently.

Choose the right home layout for your design

The surfaces that are exposed to the outside are reflecting how much heat can leave or enter your shipping container home. The more surface area you have, the more insulation you need. The most efficient shape is one large square or rectangle because it minimizes the ratio between internal space and surface area. Some designers love to use shipping containers creatively, and they make homes in irregular shapes. The more irregular your home, the more insulation you will need, so if you don’t really need to be fancy and show off chose a simple home design.

We hope that this article will help you choose better the type of shipping container you will get, the right materials and give you an idea on what you need to take in consideration before starting your insulation project for your shipping container.