Recycling Steel Shipping Containers
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Q: We have a lot in the south-eastern side of Mexico, near the ocean. It is a fairly remote area at this time and power and building/worker's etc are not in great abundunce. I think the container building may be a great alternate. Just a couple of question's: How do they fair in the hotter area's? Also, we were hit by Cat 5 hurricane a couple of year's agoand I understand these may be a good structure for these area's? And finally, the cost to refit and finish a container in comparison to regular construction cost's?

A: (Kelly) Steel container homes need to be insulated to be comfortable in practically any climate, so yes this is essential in that area of Mexico. The containers themselves are virtually indestructible, so they should be able to handle hurricanes pretty well. Of course large areas of glass, or other parts of the structure that may be added onto it might be more vulnerable to winds.

Cost comparisons are bit difficult to make, especially in Mexico where labor tends to be cheap, so new construction can be fairly economical. The container(s) would need to be purchased, transported to the site, and then retrofitted to become a home...so there may not be much difference cost-wise in the end.

Q: We are seriously considering building a home from shipping containers. One thing that concerns us is how to insulate it. The 'finished product' will have a traditional home look, with hip roof and siding of some sort. We are thinking that some type of spray foam polyurethane insulation would be good for the inside, but what about the outside? Since the house will have siding, we assume that ceramic paint would be pointless. what would you consider to be a good insulator for the outside walls, if any is required?

A: (Kelly) As long as you are going to put siding on the outside anyway, I suggest that you also add insulation there. The SG Block folks use a commercial insulation panel material that you  can see being installed in the middle of this article.

Q: I really like the idea of using heavy strong steel boxes as the structural framework of a home, and it seems to me that containers would have one massive advantage - once they are in place and welded together (with plates welded over any gaps/joints, etc.), we would have a completely dried in and structurally sound box in which to work.  Anyway, as much as we like the utility of containers, they lack a lot when it comes to aesthetics.  We certainly do not want our house or even our outbuilding to look like containers when were done, so I'm wondering about using earthbags as an exterior.  It seems to me that the earthbags would nicely compensate for the lack of thermal mass in the containers (insulating ceramic paint (assuming it actually does work) can only do so much, while the containers would remove some concerns about structural rigidity with an earthbag structure (particularly in the mind of a building inspector).  Does this seem like a reasonable approach to you?

To consider the practicalities of this - how would you tie the earthbag exterior wall to the steel wall of the container?  I was thinking that it could be done via the barbed wire - either by welding the wire at points to the container walls so that your wire in between bag layers was tacked to the wall every so often, or by attaching something like D-rings to the container walls and running the wire between the layers of bags through that every so often.  Does that seem reasonable?  Do you think that exterior buttressing of those 40' long vertical walls would still be required?  Without buttressing, I'd be a bit concerned about the potential "pull" of the earthbag walls on the steel side walls of the container.  Also, I know that in brick veneer construction, there is nearly always a narrow air space between the framing sheathing and the brick - would something similar be required in this case, or could the earthbags be brought flush to the container sides?  On another front, do you think it would be possible to use earthbags to create a roof surface on top of the containers?  I'm picturing something very much like a typical adobe structure, with a parapet and a flat roof (well, apparently flat - it would naturally need a crown for water runoff).  What sort of material would you recommend as a finish for such a roof - concrete stucco?  Or would it be better to just pour a (relatively thin) concrete surface on the roof?

A: (Kelly) Much of what you say about containers is true. They do have to be insulated in order to be used for comfortable habitation. I have my doubts about the insulative paint being sufficient for the job, especially since I have read rather disparaging reports about the efficacy of this paint over time. Another approach to insulation (besides commercial foams and rigid boards) might be to use earthbags with an insulating material as fill. Rice hulls, crushed volcanic stone, perlite and vermiculite are possibilities for this.

Attaching the bag wall to the container should be fairly easy to do, either with what you suggest or possibly running loops of wire (it wouldn't have to be barbed) around one entire bag and through  an eye welded to the container. If this were done on a grid of about every 4 ft. (both vertically and horizontally) I don't think that any buttressing would be required.

With brick veneer, the air gap is for breathability. Steel containers don't breath at all, which is another reason to put the insulation on the outside; otherwise the cold steel would likely condense moisture on the inside. With earthbags, I don't see the need to leave such an air gap.

Just how you treat the earthbag wall depends on various factors, especially how you design the roof over the building. Probably the best thing to do would be to design the roof with a large eaves, so that the earthbag walls are protected from the rain. If this is done, then the earthbags can be left breathable with an earthen or lime plaster.

I would advise earthbags on the roof only if they are covered by another roof and are there merely for insulation. I would not advise a flat roof and parapets, as this would increase the likelihood of problems and maintenance issues over time. You do need insulation on the roof (even more than the walls). If you really want to proceed with a flattish roof, then perhaps some combination of a moisture barrier (like EPDM) and concrete would do.

Q: My wife and I are starting a project for a small Montessori school in Ensenada, Baja Califonia. We are looking at inexpensive building alternatives with a recycle/re-use principal in mind. We have decided to use reclaimed ISBU shipping containers, but we are now faced with insulating these containers. We would like to keep the recycle/re-use principal, but also keep costs low. I am considering doing a papercrete formed wall, about 4" thick, and 4'x9' that would be poured flat (tilt up), the form would be made of galvanized steel studs, and would be used to attach the formed wall to the container wall/frame, from the interior. Would this size/thickness of a wall be light enough to be carried by two/three people?Iis there any way these could be formed vertically in place?

A: (Kelly) While in theory what you suggest might be possible, I can foresee some difficulties and reasons that it might not be your best approach. Such PC panels would have to be formed horizontally, outside the container and thoroughly dried before being moved inside. 4" of  PC provides only about R-10 insulation at best, which is not much to withstand the radiating intensity of hot metal. Add to this the fact that these interior panels would be diminishing space that is at a premium and needs to be preserved for other functions. I think that a much better approach to insulating shipping containers is from the outside. In fact I have just been communicating with a man who is currently living near Puerta Vallarta, MX and is contemplating doing something very similar with shipping containers. Some years ago he started a school there to assist kids who work at the local dump, recycling trash for a living (see www.childrenofthedump.org ). He suggested getting the kids to save the styrofoam that accumulates, crushing it into particles, filling polypropylene bags with this material, and stacking the bags around the container for insulation. Even the bags can be used or recycled ones. To further protect the bags (which need to kept out of the sunlight) and the containers themselves, we discussed the notion of covering them with plastic (maybe a pond liner, but it could be an old PVC billboard or even heavy polyethylene) and then backfilling or covering the whole thing with soil...which could be planted with local plants that grow there. Or, the poly bags can be encased with stucco netting and plastered to make the building look like any other Mexican building.

Q: What are the most common, or some of the different types or styles of, foundations used for container homes.

A: Most container homes that I have seen have been set on standard continuous concrete foundations, but this might have been a requirement of the local codes. There is no reason why they couldn't also be set on concrete piers. There are some pictures of various foundations at here.