Oak Park architect Tom Basset-Dilley is at it again.
Fresh off the success of building a house on Clinton Avenue in Oak Park that incorporated ultra-energy efficiency, Basset-Dilley decided to go the distance and build the state's first certified passive house, one of only 28 in the U.S. His new project, built for a local family on Jackson Avenue in River Forest, is nearly complete.
A passive house?
According to the Passive House Institute, a passive house is one that achieves overall energy savings of 60-70 percent over a house built to standard code, and heating savings of up to 90 percent without using technologies such as photovoltaic or solar thermal hot water systems. With super insulation and air-tight construction techniques, passive houses aim to minimize energy losses and maximize energy gains by using a heat and energy recovery ventilator that helps a house maintain and use energy and heat created within the dwelling instead of venting it out.
Popular in Europe for generations, passive house building techniques are beginning to gain steam in the U.S. as architects, builders and homebuyers become more sensitive to their impact on the environment. Always interested in green building techniques, Basset-Dilley decided in 2010 to become a certified passive house consultant because of the impact such homes have on the environment.
"My whole motivation is architecture for a healthy world," he says. "Not only does this house meet passive house standards, but we've gone above and beyond and made it as healthy a home as you can build today. We expect passive house certification around the first of 2013, and we also are part of a pilot program called Healthy Child, Healthy World that limits the use of chemicals in interior materials.
"It's exciting to have a house that's healthy for the planet inside and out."
Basset-Dilley points out that there are three basic requirements of a passive house: get overall energy consumption below a certain level, reduce heating demand to a certain percentage of what a house built to code would be, and keep air circulation below a certain level. For example, a normal home built to code would have about six air changes per hour, and a passive house is required to keep that level at .6. The house on Jackson Avenue is testing at about .3, a massive reduction in air circulation due to the passive house construction methods.
The owners were interested in building an extremely energy efficient home and stumbled upon Basset-Dilley through local web-resource Mom Mail. Within months, they found the perfect site in River Forest, a partially demolished home that offered up a great lot for a new build.
Even the deconstruction of the existing structure was completed according to green building practices, with most materials donated to the Rebuilding Exchange and exterior bricks used for retaining walls around the basement windows. The walls of the new home are built of Logix, which is insulated concrete blocks that Basset-Dilley likens to giant Legos. With insulation that does not contain formaldehyde, the walls are about 18 inches thick, quite a difference from 11-inch thick walls in a home built to code.
The home's siding is Smart Side by Louisiana Pacific and is designed to ventilate, with a rain screen that essentially creates a breathable wall. The siding has a 50-year finish warranty, is impact resistant and is made of wood.
Basset-Dilley notes that the healthy aspects of the home were not only a goal in the finished product, but also in the construction process.
"Whenever I can use wood, I use wood," he says. "I'm a real convert to the siding because wood is renewable, and in cutting the siding on site, there is no silicone dust like you might have in other siding products. Our cabinets and the insulation also contain no formaldehyde, and we used no-VOC paint throughout the project.
"Our contractor was Brandon Weiss of Weiss Building and Development, and I've never seen a contractor so forward thinking on health issues. I have been, too, but he brought me to another level."
It was important for the owners that the dwelling fit into a neighborhood of traditional homes, and Basset-Dilley achieved that with a similar exterior shape and footprint conducive to other area homes. The interior also lives up to local standards by incorporating focus on the environment a la Frank Lloyd Wright, while also offering comfortable living space for a family with children.
Warm wooden cabinets in the open kitchen, optimally place windows and a striking two-story staircase with linear rails that Basset-Dilley intentionally designed to resemble the lines of a forest, bring a sense of the outdoors into the home.
Basset-Dilley spent years on the Historic Preservation Committee in Oak Park and is a big fan of Wright's work. He notes that passive house construction fits hand in glove with what Wright was doing a century ago.
"What I realized is that way back when, a lot of the ideas we see in older homes, like overhangs and window sizing and placement, were incorporated in the design because we didn't yet have artificial ways of heating and cooling homes," he says. "Frank Lloyd Wright coined the term 'organic architecture' and meant it in the aesthetic sense. I've studied that and taken it into the environmental and health areas."
Building a better world
Basset-Dilley stresses that passive house construction is not necessarily more expensive than building up to standard code. In fact, that is one fallacy that he believes the Jackson house turns on its head.
"This house cost us roughly $175 per square foot to build, and we built it from the deconstruction on up in seven months. The big message here is that it doesn't take longer or cost more to build a passive house. When you include the costs savings of operating the home over the life of a mortgage, a passive house is not more expensive. I'm very excited to spread the word that conservation is possible."