When designing new buildings, the decision to go green is easy. To some extent, it’s even required. But renovations can be more challenging. Depending on when an older building was constructed, adding a layer of environmental responsibility may be difficult and expensive – or a natural complement to what’s already there.
In the U.S., we can define several distinct architectural eras in terms of environmental attitudes. Prior to 1950, buildings were energy efficient and responsive to their environment – within the limits of available technology – because they had to be. Air conditioning was not yet readily available, and natural lighting was still the default. Homes and office towers from this time period take advantage of cross-ventilation and solid construction to maintain a comfortable temperature. Light wells and plentiful windows minimize the need for electricity consumption during the day. Modern upgrades can often be integrated fairly easily, because they fit the design philosophy that’s already there. Only the technology has been updated.
From the early 50s through the mid-70s, American architecture entered an environmental dark age. Climate control technologies were easily available, and the energy to run them was cheap. These designs deliberately flaunt the independence and disconnection of their internal environments. It’s a sort of technological triumphalism in which a building’s climate can be shaped entirely by the human will – with the help of a great deal of electricity. Large single-pane windows leak heat and energy, but can’t be opened to let in a breeze. Interior rooms, entirely window-less, depend on lights to be usable at all. Heating systems are turned on for half the year and air conditioning for the other half, with no break even on the mildest days. Environmental upgrades usually focus on replacing windows and climate control systems with more efficient modern equivalents. However, without major renovations, there’s a limit to how far these buildings’ energy dependence can be reduced.
In 1973, OPEC’s oil embargo brought an end to cheap energy – or at least to architecture that took it for granted. Designers finally realized that they were working with limited resources. Innovation, and a willingness to invest up front in better insulating materials, quickly followed. Buildings from this era can still benefit from retrofits with more recent technology, but generally have the infrastructure to support it.
Over the last decade, programs such as LEED certification have encouraged an increased focus on energy efficiency in architectural design. Efficient lighting and climate control systems are slowly but surely becoming the default in new construction. More innovative solutions, such as green roofs and integrated power generation, are also becoming more common. These new buildings set a standard that older buildings must sometimes struggle to meet. Of course, renovation starts out with an inherent advantage from an environmental perspective: new construction is itself a major source of energy usage and waste production. And those of us who love historical architecture, and hope to preserve the personalities of our cities and towns, are glad of the excuse to keep the old buildings – but make them a little more green.
Image courtesy of Barbro Uppsala on flickr