43 13 Cross Loops What if building materials became nutrients for biological or technical cycles? Cradle-to-cradle thinking proposes redesigning building materials so they can be reused or repurposed after they are reclaimed from buildings, creating value and products out of used material. Materials could be biodegradable or endlessly recyclable—resources that are used and reused rather than discarded and then extracted or produced anew. 1 In addition to the cyclical logic of recycling, materials could also loop back into other cycles of production. Building materials that break down into agricultural and industrial nutrients would help eliminate waste. Textiles or fiber panels can be designed to biodegrade so that they can be reused as nutrients. Other materials like glass and aluminum can be designed to be recycled multiple times, though the energy intensity of the recycling process needs to be taken into account. Cycling can work in both directions: just as construction components could be transformed into agricultural nutrients, packaging, industrial, or agricultural by-products could become building materials. 1 Michael Braungart, “Upcycle to Eliminate Waste,” Nature 494 (February 14, 2013): 174.