Phipps debuts ambitious 'living' building project
You can see tomorrow today. And you don't have to leave Western Pennsylvania.
Phipps Conservatory and Botanical Gardens has just opened to the public its new Center for Sustainable Landscapes, a three-story office building that is modest in appearance, but extraordinarily ambitious in what it seeks to accomplish.
“We believe we've built the greenest office building in the world,” says Richard Piacentini, executive director of Phipps, and he makes that sweeping comment in a very matter-of-fact way.
“Green buildings” and “environmental sustainability” have become watchwords among architects and planners these days, as these two groups have helped lead the way in embracing the ideology of environmentalism.
But this $15 million building goes way beyond what those words usually mean.
If it operates as planned, it will, on an annual basis, provide on-site all — or nearly all — of its own resources for heating, cooling, ventilation, lighting and water without requiring a net input of energy or resources from the outside.
While buildings like the David L. Lawrence Convention Center and the under-construction PNC headquarters Downtown are justifiably celebrated for being “green” because they drastically reduce their consumption of energy, the Phipps building all but eliminates the need for outside resources.
It will be one of the first of what people are now fond of calling a “living building,” the idea being that, just like a tree, a building can draw the resources it needs from the air, water and soil around it. That probably won't ever be possible for most buildings, but it is still a huge step forward in energy conservation, and Phipps is determined to show the way.
Here's how it works: First, the building is arranged to take advantage of its site. It sits on a steep hillside behind the conservatory with the long side of the building facing south to the sun. There are sunscreens over the windows — a technology as ancient as awnings but shamefully neglected in the years of cheap energy. They permit the low-angled winter sun to penetrate to the core of the building, helping provide light as well as heat, but they block out the high summer sun.
The building boasts a large three-story glass-walled entrance atrium. The hillside side of the atrium is a big exposed concrete wall that will eventually be covered with deciduous Virginia creeper. The vines will absorb heat in the summer, but after the leaves fall in winter, the concrete will absorb solar heat during the day and slowly release it at night.
After that, though, the technology that makes a building “living” can get mind-boggling. The walls contain packets of a high-tech, soy-based gel that absorbs and holds heat after the temperature reaches 73 degrees, but releases the heat when temperatures fall below 73 — exactly what you might want for season-round, or even day-long, heating and cooling.
Most of the rest of the heating and cooling relies upon an on-site group of 14 500-foot-deep geothermal wells linked to a highly efficient electric heat pump. In simplest terms, the heat pump will cool the building by taking heat out the air and sending it down the wells in the summer, and heat the building by bringing heat up from the wells in the winter.
Phipps expects large arrays of photovoltaic solar cells to provide enough electricity to run the building on what they call an “annual basis.” That means that when there isn't enough electricity generated on gray winter days, the new building will “borrow” electricity from the conservatory on the hill above it. Then on hot summer days, the solar panels will produce more than the offices need and excess electricity will be sent up to the conservatory, reducing the conservatory's use of electricity purchased from outside.
This is why they talk these days about “net zero” energy. There may still be a need for supplemental outside energy on some days, but, if everything works as planned, it will pay back — or more than pay back — in the summer what it borrowed in the winter.
The new building also aims for “net zero” water use — although health regulations make that harder to achieve. Rainwater for nearly all the building's needs — including watering plants and flushing toilets — will be captured on site. However, as is required almost everywhere, Phipps must use city water for drinking, dishwashing, handwashing and so on, so there is still an unavoidable input of an outside resource there.
Someday, that may change, too. Phipps is demonstrating solar distillation devices that produce pharmaceutical-grade water. The pure water is used to water the conservatory's orchids, as city water contains chemicals that orchids don't like.
The new 24,000-square-foot building centralizes Phipps offices that were previously at other locations. It was designed by a team of architects and engineers — almost all of them local — led by The Design Alliance, a Downtown architectural firm. All the engineers, landscapers, architects and consultants met frequently so all systems were essentially planned simultaneously.
The building is surrounded by what will soon be a hillside garden of entirely native plants — all plants that can be found within 200 miles of Pittsburgh. And the skin of the building is salvaged barn siding, all from this area, too.
The theory is that a “sustainable” building should be every bit as much a product of its location as a healthy tree.
John Conti is a former news reporter who has written extensively over the years about architecture, planning and historic-preservation issues.