I'm not usually impressed by people making products or buildings out of trash. Not because it isn't a good idea -- it clearly is -- but because most such projects don't scale well. They're nice one-offs but can't be set up for mass manufacturing. There are several exceptions, though, and I recently stumbled upon another one: the Casa Ecologica de Botellas Plasticas in Argentina.
I was on vacation, going to Cataratas Iguazu in northern Argentina to see the amazing waterfalls, and it just happened that next to my hotel out in the countryside was a sign saying "The House of Plastic Bottles! Visit it! Surprise yourself!" Always a sucker for a quirky roadside attraction, I trotted down the little dirt road through the trees to check it out. But when I arrived, I found that Alfredo Alberto Santa Cruz and his family have built a prototype for a modular-assembly, comfortable tropical home that costs next to nothing and diverts hundreds of two-liter plastic bottles from landfills in the process. What's more, it seems like a design that will scale reasonably well, because it uses cheap common parts, can be built either cheap-and-temporary or sturdy-and-permanent, and can even pack flat and ship in a pickup truck.
Mr. Santa Cruz first got the idea when making his daughter a little playhouse in the front yard. The construction was surprisingly robust, so he thought "hey, I'm on to something!" and built a full-sized bedroom cottage with an actual bed, three chairs, shelves full of toy cars, a broom, an octopus mobile, and even a fake hanging plant ... all out of plastic bottles with some wood framing and a few nuts and bolts!
The walls were made from columns of two-liter bottles, some cut in half to slip over other ones that were screwed into the adjacent bottles, so that all joints were fat-end to fat-end, no necks. This avoided too much empty space and also made all bottles interlock (in addition to the screw connection). These columns were assembled into a wooden frame to form panels, and then the panels were twist-tied together with wire to assemble a house. Windows were made with CD jewel cases in a variety of color tints.
The family showed me how they could make the structure more sturdy if they chose, by filling out the fronts and backs of panels with concrete. Laying the panel flat and pouring concrete into it around the bottles is a cheap way to make concrete walls without forms, and using a fraction as much concrete as slab construction. The air in the bottles also makes the concrete wall insulative, just like Rastra and other pour-in-place insulated concrete forms. In northern Argentina's mild climate, however, the walls of bare bottles were rather nice, because their translucence admits plenty of natural light, and the small gaps between bottles encourage natural ventilation. For the non-concrete walls, Mr. Santa Cruz also mentioned the idea of filling the bottles partly with earth, for a makeshift kind of fireproofness -- a fire will first shrivel a bottle, then melt it enough that it splits and the earth spills out, smothering the fire. Pretty clever.
But I thought the most clever part was actually the roof, made of tetrapak boxes (the polyethylene and aluminum lined paperboard boxes that you get juice or wine or milk in), flattened into shingles and laid aluminum-side up for high solar reflectance. The resulting roof will keep you cooler than most American roofs! And the re-use of the tetrapaks is a particularly resourceful solution because while PET, the material used to make plastic bottles, is the most commonly recycled plastic, tetrapaks aren't really recycled even in most of the developed world. (They are technically recyclable, but it's not cost-effective for the vast majority of municipalities.)
Unfortunately, said Mr. Santa Cruz, the tetrapacks only last four to five years before falling apart from the rain. But he covers them with a layer of plastic bottles cut to look like terra cotta tiles, and guesses the combination should last 20 to 30 years, and still keep the sun's heat off well. (If you put a second layer of bottles and tetrapak underneath them, it'd be insulated, too. But on the day I was there it didn't need it.)
I was pretty impressed with all of the ways plastic bottles were used throughout the house. The platform for the cottage stood on more two-liter bottles filled with earth and stacked horizontally rather than on end. Some bottles were chosen for their color or painted to make little flower patterns in the wall. Even the stairs were made by stacking the earth-filled bottles to different heights. And the Santa Cruz family even turned bottles into furnishings. The chairs and bed were constructed the same way the walls were, but with the stacked bottles placed parallel rather than serial to achieve structural strength across a wide area. (In fact, I found them sturdier than the normal wooden chair back in my hotel room.) Fairly thin cushions on top made the chairs decently comfortable. The family also made decorations and toys out of bottles, many of which were delightful and clever, including toy cars with working wheels. Alfredo's father showed me how they made a robust broom by making the "straw" strands with slices of plastic bottle (which they made a little jig to cut effortlessly), twisted into tight springlike coils.
There have been many houses made of bottles in the past, but they've almost always been glass bottles. The use of two-liter plastic bottles is a novel variation, enabling different constructions and uses. The modularity and transportability open up many possibilities. They system would be easy to load onto a truck for delivery to customers, or even to create a portable demonstration for local schools and towns.
Mr. Santa Cruz hasn't gotten funding for his project, but he deserves to. Right now, he and his family fund the hobby by selling various knickknacks made of recycled bottles and cans. Even these are creatively done -- they made unbreakable bags from the plastic straps used to bind crates, lumber, etc. during shipping; bracelets and purses from can pop-tops; cute little teapots and yerba mate pots made from old aluminum cans. These novelties are fun, but Mr. Santa Cruz's building system could let a huge number of people all over the world create their own homes for next to nothing, and eliminate a ubiquitous source of waste at the same time.
I suggested he set up an account to receive PayPal donations for his work to take it to the next level, and he did. Donations can be sent to lacasaecologicadebotellas [at] hotmail [dot] com. If you speak Spanish, you can contact Mr. Santa Cruz at the same address. Even if you have no desire to contribute, he's also interested in sharing ideas with people across the world.
Dark 2 liter plastic bottles can be used as solar absorbers. Plastic bottles are used also to pasteurize water around the world. Plumb a bottle wall or roof and you could have solar hot water like that guy in China made from glass bottles for his mother.
This is one reason why I like Recyced Solar
A wonderful use of waste materials, I would love to see things like this happen in New Zealand but the bureaucracy in this country would consider we are too well developed to use this or other innovative methods of construction... however with the world order changing we too could go back to our roots and become famous again for our Number 8 wire technology...
I hope so.
Given that such plastics degrade naturally over time, and at a higher rate when exposed to heat, light and temperature fluctuation, is this perhaps not the solution it seems?
Great work! I work in the propane business and I was wondering about the use of old 20 lb propane cylinders for building structures. We presently stack them using plywood sheets between them and we can walk on them no problem - very solid. With some easy cleaning they can be rendered safe from fire...
While this sort of recycling is important and interesting, a group that is doing some really cutting edge recycling is SOIL (Sustainable Organic Integrated Livelihoods). They work in Haiti to install community toilets that recycle human nutrients into fertilizer. Perhaps not as pretty as buildings made of bottles, but exceptionally amazing recycling possibilities!