"Wall cladding" refers to materials that cover the outside of a building's exterior walls. The materials cover the building but do not contribute to its structural integrity. Because wall cladding does not support a roof's weight, you can choose any material as long as it is not too heavy for the wall's components that support the roof.
If you want to use metal but are afraid of the environmental impact of your choice, consider copper. Buy copper cladding because this metal is not in a significant shortage compared to some other natural metals. According to the Copper Development Association, copper panels can be combined to create flat siding for the outside of your walls. You can also research the impact of copper cladding on your green heating and cooling strategies for the entire home.
If you like concrete, precast concrete may be an option for the sides of your home. Precast panels don't just work for the exteriors of commercial buildings. You can order a concrete home to be clad with precast panels and later transform the outside of the building with spray-on concrete coatings. These coatings, often used to surface decks and patios, can simulate effects of natural stone, brick, tile and other building materials.
Wine Tank Wood
To restore an old home with wood that has a natural, aged look, consider using reclaimed wood as an exterior wall cladding. The Green Thinkers website offers an unusual suggestion in its archives of green cladding. Find redwood originally used for wine tanks, in which wine was stored and aged. Have the redwood lumber repurposed by a lumber company into uniform pieces for your wood exterior. These pieces almost resemble a log cabin. Because redwood trees are so hardy, you can get many years out of reclaimed redwood cladding. You must, however, protect redwood panels against the elements.