Container forklift picks up the container from the top 2 corners

Container forklift picks up the container from the top 2 corners

I was recently talking to a customer about moving around 20' containers and different ways to do that.  He was asking how we do it, what kind of equipment we use and what options he would have to move them around himself.  It is a great question because the 20's are perfect for moving around and being more flexible than the 40's, particularly on construction sites or other places where you need temporary, secure storage.  20' containers are flexible and durable, so they can be moved in a variety of ways. 

In the container yards and depots, container forklifts are the most common way to move them around, like pictured above.  The forklift picks up the container by the 2 corner castings on the top of the container that the forklift can reach when picking it up from the side.  These forklifts can also extend the arms out to pick up a 40' container as well.

If you are having your container delivered to you, an easy way to have it moved to the right spot is by having it delivered on a tiltbed truck.  The truck backs into the spot where the container will go, the back of the trailer tips down.  There is a winch that lowers the first end of the container off the truck.  Then the driver pulls the truck forward and uses the winch to finish setting it on the ground.  However, to do this, we need enough room for the truck to maneuver.

Here are two one-trip 20' containers loaded on a tiltbed truck, all ready to be delivered.

Here are two one-trip 20' containers loaded on a tiltbed truck, all ready to be delivered.

20' containers with forklift pockets. 

20' containers with forklift pockets. 

The container floor is made up of steel cross-members with a wood floor over it.  The underside of the flooring is coated to make it moisture and bug resistant.

The container floor is made up of steel cross-members with a wood floor over it.  The underside of the flooring is coated to make it moisture and bug resistant.

More standard style forklift can do the job.  However, a few modifications are in order to make that go smoothly. 

  1. 20' containers come with forklift pockets.  However they measure 69" from the inside of one pocket to the inside of the other pocket.  This is noticeably wider than what most standard forklifts can handle. 
  2. If your forklift can't spread out that much, the other option is fork extensions.  If you have forks (with or without extensions) that are at least 8' long, then you can pick up the container from underneath it. If your forks are less than 8' long, the forks will come up through the floor of the container, and that would not be good.
Top corner casting

Top corner casting

There are plenty of other types of equipment that can move a 20' container:  backhoes, cranes, tractors, or really anything else that can move 5,000 pounds.  Containers have corner castings on all 8 corners of the container.  You can chain to those castings by running the chain through the holes on either side of the casting and/or the hole on the top of the castings on the top of the container or the bottom of the bottom castings.  From there, you can lift or drag the container around from there, depending on the capabilities of your equipment.

If you want to stack your container, you can use any of the different types of equipment listed above.  Standard 20' containers are 8'6" high, so you will need to have equipment  that can lift that high.  When you are placing them on top of each other, stack them corner to corner.  The corner posts of the container and the floor are where all the strength is.  The walls and roof are not as strong.  Also, the corner castings drop a little lower than the rest of the floor and a little higher than the rest of the roof.  When you stack containers corner post to corner post, you can see a space between the containers. It is a good way to know you have them lined up right.

No matter how you move and/or stack your containers, please make sure you check out that the equipment you are using is rated to handle the weight of the container.  That includes chains.  Also, be very careful that no one is in a location where they can be hurt by the container if your calculations are not 100% correct.  5,000 pounds of steel is very heavy.

Bottom corner casting (with some ice)

Bottom corner casting (with some ice)

One-trip 20's stacked up.  Notice the space between the containers since they are stacked corner post to corner post.

One-trip 20's stacked up.  Notice the space between the containers since they are stacked corner post to corner post.

Vapor barrier installed with steel studs

Vapor barrier installed with steel studs

We are lucky to have another guest blogger today!  Today’s post comes from a Super Cubes client in Florida, Sterling Cox, founder of Southworth LLC, who is converting a one-trip 20’ container into a prototype living space, to be used as a production model. You can follow the pictures they are posting to Instagram at  http://instagram.com/swlivingspaces#. Or, if you’re in the Jacksonville area, they’ll be debuting the finished product at a festival called OneSpark from April 9th-13th (www.BeOneSpark.com). Like so many other container projects, they are balancing their goal of using green building practices with being cost-conscious and also energy efficient.  They recently added a vapor barrier to the container before insulating it.

Tonight's process:

We adhered a layer of Tyvek Home Wrap to the inside of the container for the vapor barrier using 3M all-purpose spray adhesive. This process was difficult with two people, and I imagine nearly impossible with one.

According to everything I read from what I determined to be credible sources, and my neighbor Randy who has been a contractor most of his life, a vapor barrier is essential. Containers are apparently notorious for condensation build-up on the inside or “sweating,” especially in humid climates. A vapor barrier blocks moisture from entering a home. It can be a foam or some other type of insulation, or more typically, a film or sheet. Conventionally the house wrap, Tyvek or another brand, is applied to the outside of a “normal” home being built, stretched taught and stapled in place before the siding goes on.

Reasons why we chose Tyvek:

  1. It is the easiest to obtain through a retailer, and by far the cheapest option. The spray adhesive is necessary to have the film adhere to the wall as it gets rolled on.

  2. To extoll the green benefits of our decision to go this route, I’d say the wrap itself is recycleable, a #2. This is a polyethylene, same as a milk jug, shampoo bottle or Smart Balance tub. The apparent R-value is non-existent, being that it is the thickness of construction paper.

  3. The simple fact is that it was a necessary step in construction.

Why it is non-green:

  1. Tyvek is manufactured by DuPont, a large chemical corporation, one that is undoubtedly manufacturing many products that, though useful, have difficulty diffusing into the ecosystem as it were. So be it. Sometimes awareness is all that you can offer.

  2. The spray adhesive is manufactured by 3M, and simply by its odor and effectiveness, it is apparent that it is far from a green product. They advertise low VOC, though. Note: if you use this or any other spray adhesive in a container, cover your hair and wear long sleeves and pants. Wash your hands with mineral spirits afterwards.

If I had to go back:

I’d use Typar or HomeGuard house wrap. Both companies claim to have recycled content in their product, are part of the Green Building Council, and at least mention LEEDS in their respective websites. Another credit is that both companies actually address some sort of environmental awareness, whether or not it’s a marketing ploy. Note: both brands are more expensive than Tyvek.

As far as adhesives go, I’d order one that was from a smaller corporation, and had some sort of green credential. In my research, I find that at least attempting to sound green deserves a little credit. As I mentioned, being under a time constraint, we opted to use what we can get at the store as opposed to waiting for an order to be delivered.

Really if I had to go back:

I’d do some more research and find a spray-on vapor barrier. Naturally I’d look for something green, but even a petroleum-based product would be justifiable. The FoamIt Company manufactures a DIY spray foam that is apparently soy-based, but after reading the fine print it seems a bit dubious. No matter, any soy insulation is actually petroleum-based with soy content added. This kit offers 600 sq. ft. of 1” foam, which is very close to the amount needed to cover the two long walls, back wall, and ceiling of a 20’ container. It’s closed cell, so it’s an effective vapor barrier. The 1” of foam has a rating of R-7, which is a good start in conjunction with another type of insulation. The kit is $630, so cost is a factor. After you begin spraying, it’s apparently unusable after a month.

When all is said and done, I’ve spent under $150 to have a vapor barrier that is trusted by industry professionals and experts. I detested every minute of the application, the aesthetics of it severely irritate me and I honestly cannot wait until it is covered by insulation.

Postscript:

Certain types of readily available primers such as Zinsser’s BIN or Sherman William’s Moisture Vapor Barrier have acceptable perm ratings per most building codes, between 0.1 and 1 perm. Really really going back, I’d use something along those lines.

Another option I only briefly explored, but might end up being a very effective option would be to use some sort of spray on bedliner used to coat the beds of pickup trucks such as Rhino Liner.

You can email Southworth LLC at swlivingspaces@gmail.com.

Have you installed a vapor barrier on a container?  What worked and didn’t work for you?  What advice would you have for someone planning on applying one?

Below are some pictures from the project.

24' modified containers stacked up

24' modified containers stacked up

Last week I visited our Chicago shop to meet with some customers and check on a few projects that are going on down there.   The 2 projects we have currently there are both industrial projects.  While the containers involved will be used for completely different purposes, there were some similarities between the projects that might apply to a wide variety of project out there.

Both projects were designed to store sensitive equipment in rugged environments.  One project was going to need to brave extreme heat and cold whereas the other were multiple containers that would probably not move after they were in place, but would need to suit a wide range of temperatures.  Both needed heavy duty HVAC systems and insulation to ensure that the interior temperatures stay constant.  Both project also needed to have custom holes for equipment to come in and out of the container. 

The also had some differences.  One project had a very specific length they needed – 24’.  No more, no less.  The other project had very tight space requirements, so we used 10’ containers.  While both are custom lengths, the 10’s are a more common “custom” length so we were able to use containers called “duo-cons”.  Duo-cons are two 10’ containers that are built end to end in the factory.  Both ends of the “20’” container have doors and where there should be doors to separate the containers, there are not.  Instead the walls are tack-welded inside the container so when we get the container in the shop, we can cut the two containers apart and weld the ends in place.  Also, the 10’ containers needed to have special flooring to work well with the equipment going in the container.  The larger container needed only an epoxy floor that was applied over the existing floor.

Here are some pictures of the different projects so you can get an idea of what these projects look like.