The design and construction of a new house according to environmentally thoughtful, sustainable, "green" practices offers many rewards but entails a variety of ironies, compromises, frustrations, and practical problems as well. This website is intended to document the process involved and lessons learned in building this lakeside house in Evanston, Illinois. The owners, architect, and builder hope to encourage and assist other owners, architects, and builders with "green" intentions who are considering a project in this direction.
During the actual design and construction phases for this house, a website was developed to keep track of the information being gathered to answer the many technical questions involved in "green" building and to follow the progress of the new house. This new website provides a more streamlined introduction to the design and construction issues addressed and includes post-construction observations as well as links to the original website.
OVERVIEW--Fighting global warming
The scientific evidence is clear that the earth is warming and that human activity--mainly the burning of fossil fuels--is a primary cause. Signs of global climate change are already apparent: disappearing glaciers, increasingly severe heat waves and droughts, extreme weather events, dying coral reefs, disrupted ecosystems, and more. Strong action to cut global greenhouse gas emissions is needed now if we are to avoid irreversible damage to our planet.
Individual citizens and governments at all levels have important roles to play in addressing the enormous challenge of climate change. Reducing energy consumption, increasing our reliance on renewable energy sources, making use of energy-efficient technologies, setting high energy performance standards--all are important strategies for reducing greenhouse gas emissions.
With this in mind, a major goal in building this house was to make it as carbon-neutral as possible. Although performance results to date are more modest than projected originally, the house has achieved a significant level of energy efficiency. In their daily monitoring of their energy usage, the owners find that they are using 70 percent less electricity and 60 percent less gas than they did in their former 1920s house, which was of comparable size. And in a home energy audit, the house earned a Home Energy Rating System (HERS) Score of 92.7 for certification as an ENERGY STAR home.
[When the audit was conducted, in 2003, the higher a home's HERS Score, the more efficient the home. A score of at least 86 was required to meet ENERGY STAR standards at that time. In 2006, the HERS Index replaced the HERS Score. With this rating system, the lower the value the better. A HERS Index of 100 represents the energy use of a standard new home, while a net zero energy home has a HERS Index of 0.]
Outlined below are the major aspects of design and construction that have contributed to the high energy performance of the house.
Designing for efficient use of land and energy
Although the new house is relatively large (4,000 square feet, plus basement and garage), an obvious design objective was to take full advantage of the site's dramatic views of Lake Michigan. The open floor plan was intended to accommodate midsized groups of people attending civic and charitable events hosted by the owners. Moreover, the house conforms to some "small house" principles, such as flexible uses of certain spaces. The first-floor guest room is used as a TV room and library, for example; the sunroom is used for small meetings with colleagues and students; and the second-floor home office could become a fourth bedroom.
Design features which contribute to energy efficiency include the vestibule (airlock) at the front entry that keeps cold winter air from entering the main part of the house, the centrally located, open stairwell creating natural stack ventilation, tall windows and skylights that provide light deep into living spaces, and orientation of major windows to the south for passive solar gain.
The house is designed to allow the owners to age in place and also to welcome visitors with disabilities. There are no steps at the front entrance, doors on the ground floor are wide enough to accommodate a wheelchair, and the first floor bathroom features an accessible sink, a walk-in shower, and multiple grab bars. The owners also made provisions to allow for the addition of an elevator, should one be needed in the future.
Reducing energy consumption
Heating the house
A highly efficient advanced combustion fireplace serves as an additional source of heat. Natural-gas-fired boilers complete the heating system.
Using renewable, recycled, and locally available materials