It all started with the goal of building an affordable, healthier, more durable, near-zero energy home that could resist natural disasters and be faster to build than a standard wood-frame house. Jack Armstrong, head of building and construction marketing for BASF, Florham Park, N.J., said it was their idea in the beginning. They wanted to include innovative chemistry and state-of-the-art construction. To accomplish these goals, they partnered with several of their customers, as well as the city of Paterson, N.J. They decided to start with the construction of one home that will be occupied by a family with a quadriplegic boy. For this reason, the three-story home also would include an elevator.

To ensure that all the criteria for the house would be realized, BASF involved two additional organizations in the project;

The basement and first floor levels were constructed with ICF concrete walls while the third floor walls are SIPS panels. Both wall systems have good insulating properties. Photo: American Polysteel

The U.S. Green Building Council, Washington, D.C., who developed the Leadership in Energy and Environmental Design (LEED) program, and the Institute for Business & Home Safety, Tampa, Fla., which sponsors the Fortified...for safer living program.

The nonprofit Institute for Business & Home Safety, an initiative of the insurance industry, is among the first to visit sites that are damaged by catastrophic natural disasters to investigate the nature of building failures. Their research is dedicated to finding ways to build more robust structures. They also influence changes in building codes.

The Paterson project now is called the Better Home, Better Planet Initiative: Near-Zero Energy Home.

LEED Requirements

It was important to Armstrong to have the home LEED-certified. This can be a complicated, involved process so he asked Chrisner Group, Hamilton, N.J., under the direction of Scott Chrisner, to provide ongoing documentation of the construction as part of the LEED certification process. LEED focuses on efficiency, sustainability, and durability so the following criteria are important:

Outside finishes included cultured stone and a cement-based plaster applied directly over the ICF polyfoam. The roof is a standing seam steel panel construction, which supports the photovoltaic system and conducts heat to the tubing underneath for hot water. Photo: American Polysteel

  • Documentation of the efficiency, sustainability, and durability of the building.
  • A high-performance building for the same budget as compared to one that just meets local building code requirements.
  • The documentation must not only include costs but also environmental and social impacts—a triple bottom line.
  • If the cost of one line item is increased, another item must be decreased in order to keep the budget the same (an integrated design process).
  • The energy required to build the house is monitored—the goal being a low “carbon footprint.”
  • Building products should be environmentally friendly.
  • Building materials should be produced within 500 miles of the site.
  • Building materials should be recyclable.
  • Building materials should be fire-resistant, pest-resistant, high-wind resistant, and have good R-values.

    • Chrisner says that there are four responsible parties involved in a building project; the owner, architect, engineer, and contractor. Each party typically covers their own liabilities and risks, so they tend not to work together. When working toward a LEED certification, however, working as a team to make decisions is critical to the integrated process.

    Fortified...For Safer Living

    Although Paterson, N.J. isn't located in the direct path of hurricanes and isn't regarded as a high tornado area, it does have occasional significant weather events so Armstrong wanted the Fortified...for safer living standards adhered to in the construction. Chuck Vance, the Fortified program manager for the Institute for Business & Home Safety, says the standards include provisions for wind, fire, and water resistance. “This house was constructed to meet 130-mph-wind-gust loads,” he says. “This isn't an issue for either ICF concrete walls or Structural Insulated Panels (SIPS) when they are constructed properly.” Their issues were focused more on the means for attaching the roof to the walls—the top roof rafter must be solidly attached to the footing of the house. As a part of the designation, the construction is visited by inspection teams that are certified by Vance's organization.

    Building The House

    Costs were kept low with contributed labor and products. The 2500-square-foot home features a walk-out basement and first and second floor levels. American Polysteel, Albuquerque, N.M., contributed the ICF forms for the basement and exterior first floor walls. The expanded polystyrene (EPS) blocks are stacked like masonry blocks (minus the mortar joints) to form the walls. Workers placed vertical and horizontal steel reinforcement in the walls as they were assembled and then pumped concrete into the center cavity to create R-30 structural walls. The builder, KBI of Paterson, N.J., used SIPS to complete the second floor walls and the roof. Andy Horgan, the director of international development for Polysteel, said that precast concrete was originally specified for the above-grade floors but the waiting time was 12 weeks so instead they decided to use Insul-Deck, an ICF lightweight forming system. “The entire process took 10 days,” he said. The floors included 10 inches of foam forming material and 4 inches of concrete slabs. Radiant floor heating tubes were placed on top of the slab with an additional 2 inches of concrete placed to cover the tubes. The floor is a total of 6 inches of concrete. The temperature of each room in the house can be regulated independent of the other rooms, helping to reduce overall energy requirements. So the floor insulation of the forms, as well as the thermal mass properties of the concrete help to maintain the temperature in each room.

    Saving Energy

    Armstrong says that reducing the energy requirements involved every aspect of the construction. Using products with good R-values is important, as is building structures with good “thermal efficiency” ratings. Thermal efficiency is a key factor in the energy equation. It's a measure of how tight a structure is. If air can easily move through a structure, its thermal efficiency is very good.

    Thermal efficiency is measured by the Home Energy Rating System (HERS)—which is a way to quantify how much air can move through a structure. Partly, the number is arrived at by performing what's commonly referred to as a “blower door test”. By placing a fan at the primary entrance of a building and sealing the space around the fan, the tightness of the structure can be assessed.

    Below: Inside the home the ICF walls were covered with drywall, as were the SIPS panels. The concrete floor installed over EPS panels has radiant floor heating tubes in the concrete. The tile floor is better than carpet for heat transfer. Photo: American Polysteel

    The HERS score for this home was 94.5 out of a possible 100 points. (With 100 being the best score at the time this house was built.) Chrisner thinks this score is possibly the highest (best) score in the country for a house. ICF walls provide good R-values and thermal efficiency numbers. Although both ICF and SIPS walls are excellent systems for saving energy, there are other factors that also are important. These include:

  • The insulation in ceilings and roofs
  • Energy-saving glass in windows and the tightness of the seal between the window and its frame, as well as the space between the frame and the wall

    • Before the standing seam steel roof panels were installed, workers attached thin photovoltaic sheets that send electricity to an inverter, which stored the power in batteries for use in the home. Water circulating in tubes just below the metal is heated by the sun to further save on energy costs. Photo: American Polysteel

  • The seals between doors and their frame, and between frames and walls
  • The efficiency of the HVAC system

    • In order to further reduce the external energy requirements for this house, there are two interesting features. Just below the standing seam roof panels there are coils circulating water that can be heated from the sun in order to reduce the energy needed to heat water. Up to 4 kilowatts of hot water will be supplied this way. Also, on the top of the metal roof panels are thin photovoltaic sheets that will produce 2½ kilowatts of power.

    Why This House Is Important

    Articles about concrete homes built in the United States usually cover high-end, more expensive homes. This home represents the other end of the scale—it's affordable, operating costs will be manageable, and every attempt is being made to keep its “carbon footprint” very low.

    Also important is the developing technology to provide buildings that can survive high-impact weather events, fire, mold and fungus, and pests, while using less energy.

    This is only one home but the lessons learned already are being used to plan a much larger revitalization project in Philadelphia—400 homes either rehabilitated or replaced with new construction.

    Organizations contributing to this project:

    The Institute for Business & Home Safety, Tampa, Fla. Developer of the Fortified...for safer living program

    The Partnership for Advancing Technology in Housing (PATH)

    The U.S Green Building Council, Washington, D.C. Developer of the LEED program

    Project Participants:

    Owner: St. Michael's Housing Corp., Paterson, N.J.

    Organizer: BASF, Florham Park, N.J.

    Architect: GRAD Associates, Newark, N.J.,

    Green Building Consultant: Chrisner Group, Hamilton, N.J.

    Builder: KBI, Edison, N.J.

    ICF Supplier: Polysteel, Albuquerque, N.M.