La Casa de Botellas, created by the Alfredo Santa Cruz family in Puerto Iguazu, Argentina, was constructed from thousands of PET plastic bottles, and was designed as “a tool for promoting ecological and social responsibility.” The surprisingly sturdy structure features a Tetra pack roof, doors and windows made from CD jewel cases — and the interior boasts beds, coffee tables and couches, all created entirely from used plastic. While no one in the Santa Cruz family is an architect or engineer, they are doing their part to save the planet by providing free home building courses in Latin American countries “to address both trash [issues] and housing scarcity.” Read more about the elements of design and the construction of La Casa de Botellas at Inhabitots.