Clearly we can’t very well tear down all of the world’s old skyscrapers for not being environmentally friendly – that kind of approach would itself be (ironic and) wasteful. At the same time, many of these buildings are projected to last for decades (or centuries) more. So what is the solution for making them green now? One rather clever proposal involves adding an auxiliary environmental layer to the existing structures that could house gardening and natural wind power production spaces.