The Concordia Language Villages, near Bemidji, Minn., wanted to create a truly innovative “green” learning center—a showcase for the most energy efficient and environmentally friendly building technologies in the world. So it was only natural that they chose to use insulating concrete forms.
Completed in mid-August, the building is the first in North America to be certified by Germany's Passivhaus Institute, the world's toughest energy standard. It significantly exceeds the U.S. Green Building Council's highest building ranking—Platinum LEED Certification—and uses only 15% of the energy that a traditionally-constructed building in Minnesota would use.
Waldsee BioHaus is a remarkable accomplishment,” says Franz-Georg Elpers, press secretary of the Passivhaus Institute in Germany. "Our generation has a responsibility for pushing the limits to achieve affordable sustainable building designs that assure a comfortable living environment.
To obtain this level of efficiency, the building has R-70 walls, triple-glaze windows and high-performance doors. The roof insulation is rated R-100, thanks to more than 28” of expanding isynene foam. That’s topped with waterproofing material and almost a foot of lightweight soil and live plants to create a “living roof.”
The exterior walls, up to a height of about 12 feet, are made from Amvic ICF with an 8” concrete core. Builders then attached an additional 8” of EPS foam to the outside of the block. The slab-on-grade foundation rests on 14” of rigid foam, also provided by Amvic.
Solar panels provide hot water; a geothermal radiant floor heating system will keep the building comfortable. The ventilation system is connected to an air-ground heat exchanger. Fresh air will travel through a series of underground pipes that will pre-cool it during the summer and warm it in the winter. The air will then be further warmed (or cooled) inside the house by a heat exchanger, using exhaust air.
“One major aspect of green building is sustainability, and ICFs are a very sustainable product,” says Gary Brown, vice-president at Amvic. “That’s in addition to energy efficiency benefits. It’s simply a better way to build.”
When Scot Smyth decided to build his dream home in the hills west of Ft. Collins, Colo., he knew it had to be extraordinary.
“It’s a million dollar lot,” says John Hatfield, the ICF supplier for the project.
“It sits on a beautiful mountain ridge, so one side has a stunning view of a nearby reservoir and the other side looks down over the City of Ft. Collins.”
Smyth build with ICFs, he says, because “I wanted a solid house built to last forever, with low maintenance, and high energy efficiency.”
Called “House at Empyrean Ridge,” the home earned Smyth “Innovative Builder of the Year Award” from the Northern Colorado homebuilders association.
Exterior walls are constructed from Quad-Lock’s Plus Panel , with 4-1/4” of foam on each side of the 8” concrete core. “It was a matter of comparing the minimal added cost of the Plus Panel versus the much larger benefit of increased energy efficiency,” says Smyth. “The value of that will only increase over time,”
Through careful planning, Smyth kept waste to a minimum. “None of the waste foam left the site,” says Hatfield. “It was incorporated into the underslab insulation, increasing the effectiveness of the hydronic heating.” The 2x8 lumber used for the footing forms was re-used for window bucks. Protected by Fab-Form, the boards were completely clean and ready for reuse when stripped.
(Click here for more on this technique.)
Smyth used “recycled concrete” throughout the job. Made from crushed granite aggregate and fly ash as a binder, it performed flawlessly. “We had absolutely no problems getting the walls poured,” reports Hatfield.
The 2,850 sq. ft. home is topped with an earthberm “living roof,” constructed of a metal pan concrete deck, topped with 11 ½” foam, 4” to 18” of growing medium, and plants.
Fly ash concrete was used for the floors as well, which have radiant hydronic heat. Baseboard and other trim was sawn at a local sawmill from standing dead trees. The exterior cultured stone material was manufactured locally.
To qualify as a “Built Green” home, the House at Empyrean Ridge needed 70 points. It scored 252. Energy Star raters gave the home a 5-Star-Plus designation, and commented that they had never seen a house so energy efficient, Smyth claims.
Currently, Smyth is in the process of designing a $1.5 million home for the adjoining lot. He’s planning on building it with Plus Panels as well.
BASF Zero Energy Home
Built in a well-established neighborhood, the newly completed “BASF Near-Zero Energy Home” in Paterson, New Jersey, doesn’t look any different than the other houses on the street. But when it comes to energy efficiency, the home’s heating and cooling costs will be about 20% of the neighbors.
The basement and first floor walls of this prairie-style home are made from PolySteel ICFs. Patrick Murphy, president of American PolySteel, says the company used both flat-wall and waffle-grid systems to showcase the versatility of PolySteel’s full line of products.
Most of the exterior walls are finished with TruWall , a textured acrylic finish designed to adhere directly to the ICF without mesh, adhesives, or rasping.
Inside the home, an ultra-efficient, in-slab hydronic radiant heat system from REHAU provides warmth for the occupants without the drafts central air can create. To support the weight of the concrete floors, designers used Insuldeck, an EPS decking system. The roof is made from Structurally Insulated Panels (SIPs).
The home uses so many “green building” technologies that the U.S. Green Building Council (USGBC) is using it as a test case for the recently launched Leadership in Energy and Environmental Design for Homes (LEED-H) rating system.
Despite all the cutting-edge technology, and its current role as a showcase home, the house is also intended to be a model for affordable living.
Klaus Peter Löbbe, Chairman and Chief Executive Officer of BASF Corporation, says, “We have constructed this home in order to inspire homeowners, builders and architects locally, as well as nationally. We want them to know that sustainable, energy-efficient and disaster-resistant homes are not a concept of the future, but a reality today. Homes based on the technologies demonstrated here are accessible to real people at affordable prices.”
Paterson has 3,000 infill lots throughout the city that have been targeted for affordable housing over the next few years, and those involved with this project hope that the Near Zero Energy Home becomes model for the city’s urban renewal efforts.
“ICFs are an outstanding material for infill projects,” says Murphy. “Noise is often an issue, and so is security. By choosing ICFs, you’re upgrading the neighborhood with a durable, energy efficient home, that also fits with the architectural character of the area. You’re actually planting the seeds to upgrade the entire city, one lot at a time.”
When Matt McCoy, owner of South River Construction, set out to build his home in the hill country northeast of San Antonio, Texas, he didn’t intend for it to become a showcase for green building.
“It wasn’t environmentalism for environmentalism’s sake,” he says. “I wasn’t trying to save the world or start a new religion. I just wanted to build the best house that I knew how to build.”
One major reason for the home’s energy efficiency is the ICF walls. McCoy’s business partner was the local Arxx distributor, and he was well acquainted with the benefits that the technology offers.
“The R-Value and effective R-performance of ICFs was a big deal to me,” he says. “The fact that it would look like every other home was a big deal to my wife. The fact is, ICF homes look like any other home except the walls are thicker.”
He then began asking himself what else he could adjust to make the house even more environmentally friendly. So he installed high-performance windows, a radiant roof barrier, and energy-star appliances. Outside, the perimeter fence is made from painted rebar, the driveway and front walk are pervious concrete, and there’s a rainwater collection system for landscaping needs.
He claims most of the “upgrades” were done for practical reasons. “I didn’t want to be on water rations when everybody else was,” he says. “The pervious concrete driveway means we don’t have runoff issues, or ruts in our yard. We have nice HVAC system, and indoor air quality is important, but I really wanted the wife to have a break from her allergies, and make it more difficult for the kids to pass germs.”
“I really just wanted to be comfortable,” he confesses. “Most people’s perception is that they will be much less comfortable in a green home when the exact opposite is true.” The home, entered in the 2005 ICF Builder Awards, won rave reviews from the judges for it’s luxurious appearance. It was featured on the cover of our Feb. ’06 issue. (To enter your project in this year’s competition, click here.
South River Construction is now a regional ICF installer. “We call it ‘high-performance construction,’ says McCoy. “It’s just defining green building in another way.”
In Every Issue Innovative ICF projects and solutions to common building questions are featured in each issue, along with product reviews, design tips, and industry-specific news.
Built in a well-established neighborhood, the newly completed “BASF Near-Zero Energy Home” in Paterson, New Jersey, doesn’t look any different than the other houses on the street. But when it comes to energy efficiency, the home’s heating and cooling costs will be about 20% of the neighbors.
When Matt McCoy, owner of South River Construction, set out to build his home in the hill country northeast of San Antonio, Texas, he didn’t intend for it to become a showcase for green building.
