Two Books on Outstanding Green Buildings

Two Books on Outstanding Green Buildings

Greenhomeby Wayne Grady, 1993. Camden House Publishing, Camden East, Ontario. 208 pages, soft cover, $15.95.

Greenhome is a wonderful account of the design and construction of a demonstration house built through Canada’s Advanced Houses program. Through this program, 10 houses were built throughout Canada between 1990 and 1992 to test and demonstrate energy-efficient and environmentally responsible design, materials, and construction practices. Because of its “low-tech” approach, the Waterloo Greenhome is considered by some to be the most progressive of those houses.

Designing and building the Waterloo Greenhome involved a team of designers, engineers, and builders led by Steve Carpenter and John Kokko of Enermodal Engineering. The target for space-heating energy consumption of the house was just 52 kWh/m² (16,500 Btu/ft²), which is half the heating load permitted in the R-2000 program. In addition to energy efficiency there were numerous other goals for the 2,500 ft² home: no CFCs, no non-recyclable construction waste, greatly improved water efficiency, etc. Even though single-family detached houses do not represent optimal use of resources, the book (and the house) provide a good model of what can be done to improve the environmental performance of this type of house.

The style of

Greenhome is inviting and easy to read—somewhat like Tracy Kidder’s

House—though the focus is more on environmental and energy concerns. Discussions of such problems as wasted space in typical houses, water issues, solid waste associated with most construction, and heating fuel choices are excellent. Some are funny as well. In a discussion of electric resistance heat, for example, Grady quotes Lawrence Solomon as noting: “It will do the job, but then caviar could substitute for rock salt in de-icing your driveway.” And to put the claim of 100% efficiency for electric resistance heat into perspective, Grady says, “Saying that electric heating is 100 percent efficient is like saying that a Cadillac is 100 percent efficient because it burns up all the gasoline pumped into it.”

Scattered throughout the book, however, are numerous mistakes and inaccuracies relating to environmental considerations. Most of these aren’t too serious, but they left us not quite trusting everything the book had to say. For example, Grady implies that the high embodied energy of concrete is because so much stone has to be crushed (when in fact energy for crushing aggregate is just a tiny fraction of the energy input). The book says Sparfil insulated concrete blocks were ruled out because they contain expanded polystyrene, which is made using pentane, implying that pentane is an ozone depleter. Numerous mentions of ozone depletion, CFCs, and HCFCs were a little mixed up. Radon’s half-life is said to be 1,602 years, while in reality it is about four days. And asphalt shingles are said to have “no recycling potential whatsoever.”

Despite these inaccuracies,

Greenhome is a good read and may be useful in introducing your clients to issues of energy efficiency and environmental sustainability.

Audubon Houseby the National Audubon Society and Croxton Collaborative, Architects, 1994. John Wiley & Sons, Inc., New York. Hardcover, $24.95.

Audubon House describes the remodeling of an 1891, eight-story office building at 700 Broadway in New York City. Upon completion, the Audubon headquarters became one of the most environmentally responsible commercial buildings in the country. Following design work by Croxton Collaborative, the building was extensively renovated in 1991-92 at a cost of $14 million. The basic renovation and design work came to $122/ft², plus another $20/ft² for unexpected underground repairs to enable fire trucks to drive on the sidewalk around the building.

As stated in the book, the goal of the project was “to design an office building that would be energy-efficient, environmentally sound, and both comfortable and healthy. The redesign would be accomplished at a competitive market rate, and the finished project would function as a ‘living model’ for future projects.” The economic constraints on the project were particularly important. The Audubon team set a maximum five-year payback for energy improvements, and a “10 percent test” was used to limit extra expense for products selected for their environmental merit. In other words, the premium cost of an environmental product could not exceed by more than 10% the cost of a similar average-priced product. The authors estimate that the renovation will reduce annual operating costs by more than $100,000.

The building’s HVAC system is complex and the graphics hard to follow, but the authors were correct not to leave out thorough discussion of this critical aspect of the project. The HVAC system is a state-of-the-art absorption chiller system using natural gas for both heating and cooling. The variable-air-volume control system delivers plenty of clean fresh air to Audubon staffers. All mechanical systems were designed by Flack + Kurtz Consulting Engineers of New York.

Waste issues are particularly well covered in the book. The project has five recycling components that go well beyond the renovation project: recycling the building (renovating an existing structure instead of building new); recycling materials from demolition (demolition contractors had to present plans for recycling); using building materials with recycled content; developing a $185,000 in-house recycling system with a goal of 80% waste recovery in the building; and establishing guidelines for the purchase of recycled and/or recyclable supplies by Audubon staff.

While

Greenhome suffers from some technical inaccuracies, EBN found

Audubon House to be extremely accurate and informative. In fact, the book presents some new information on environmental impact of buildings. Audubon’s analysis, for example, indicates that buildings and construction are responsible for a far greater fraction of the nation’s energy use than generally believed: 54% (because significant portions of energy use for transportation and industry relate to buildings).

Audubon House is one of the most important books to have appeared on environmentally sustainable design and construction. It is especially noteworthy because it deals with a commercial building and renovation instead of new construction. Hats off to Audubon and the Croxton Collaborative for both the project and the book.