Article No: 32
Wisconsin's Safe Haven Homes
By: TIRZAH TYLER
A shelter from raging hurricanes, scorching heat and drenching humidity — and even a place to store your motorcycle for the winter. Safe Haven Homes in southeast Wisconsin has tapped into a concrete building method that has proven to be one of the most effective in the industry.
Monolithic, Rock Solid
The process involved in building with removable/reusable (or cast-in-place) forms, in layman's terms, is comparable to what happens when pancake batter is poured into a waffle iron. Instead of iron, most poured-in-place removable forms are constructed from aluminum. Insulation is placed inside the forms, and then concrete is poured into the forms. Steel rebar is generally added for reinforcement. After the concrete cures, the forms are removed.
Safe Haven Homes in Wisconsin are basically constructed in this manner. The walls, ceiling and floors are created in a single pour into aluminum forms. To create the walls, concrete is poured into the forms with 2 inches of foam insulation on the inside; then 2 inches can be added to the exterior for a total of 4 inches of insulation. Ceilings are erected 9 1/2 feet tall, 6 inches thick. Floors are also 6 inches thick. The concrete cures within one day, and the forms are removed. The walls' exteriors can later be finished with stucco, siding, cultured brick or stone, etc. In most cases, Safe Haven Homes plasters interior walls and ceilings, and can also install a variety of floor coverings such as carpeting, tile, hardwood and laminate.
New on the Block?
Carl Engelken of Wall Ties & Forms in Kansas City, which manufactures the forms used in Safe Haven Homes, has worked with concrete construction for 25 years in the United States as well as internationally. He states that North American homes are still built with wood because of "cheap lumber," but that building with concrete is "the norm" in the rest of the world. For example, he states that "in Europe, if you say you're going to build a wood-frame house, they'll laugh at you, because everybody builds with concrete!"
Walls Are Us is the foundation contractor for Safe Haven Homes. According to Deb Friemoth of Walls Are Us, the contractor was involved with building foundations for 10 years before researching above-grade concrete construction. The company began looking for housing units that would be in their best interest, then researched concrete construction methods and considered factors such as strength, energy efficiency, and resistance to termites, fire and harsh winds. Walls Are Us determined that the removable form method would be best for the company to build with. "It was natural to do [above-] grade concrete," says Friemoth.
Despite its entry into the building industry as a new concrete construction method in the U.S., Friemoth stated that the company did not have any problems with code officials. "We far surpassed any codes, scoring 36 percent above energy code requirements," she said. Walls Are Us has completed two homes in southeastern Wisconsin so far. "Each house was built on speculation," Friemoth stated, mentioning that each homeowner opted for a Safe Haven Home "because of the energy efficiency, fire resistance, and it's virtually maintenance-free."
Extra Protection from the Elements
Certainly one feature that distinguishes a Safe Haven Home built with removable forms, even from other concrete houses, is the energy savings. Each household can expect to save an approximate 40 to 70 percent on energy costs. Engelken states that the removable form method with which Safe Haven Homes are built provide "substantial" energy savings. According to a study conducted by Oak Ridge Laboratories, each building in which "thermal mass [was] in good contact with the interior of the building" proved to provide a high potential for energy efficiency. Most Safe Haven Homes provide approximately an average R-value of 30.
In comparison with other concrete building methods, the walls in a home constructed with ICFs are made of concrete, while the ceiling and floor are not, causing heat absorbed by the walls to escape. Homes built with removable forms, each with concrete ceilings and floors, take full advantage of the concrete's thermal mass, creating a thermal envelope. Engelken explained that the thermal mass property in each concrete home causes the concrete walls to absorb heat in the winter and store cool air in the summer. "It works like a cooler," he said. For example, during a recent ice storm in Kansas City, part of the city lost power for 11 hours. "In the homes that were built with removable forms, while the temperature outdoors was 25 degrees, the concrete walls' temperature only dropped two degrees," stated Engelken.
In addition to heating and cooling efficiency, Friemoth said that Safe Haven Homes provide added comfort from the elements. Each house contains an air exchange unit that controls humidity, transferring humidity from humid areas of the house to areas of the house that need it. This demonstrates the versatility of a Safe Haven Home. Construction companies worldwide have built homes using the removable/reusable form method, in southeast Wisconsin, Russia and also the Philippines, Mexico and the Caribbean. In Hong Kong, some concrete housing facilities are built 16 stories tall.
Walls Are Us hopes to expand to the Florida area. "There's definitely a market there," said Friemoth. "They need houses like these to protect from the hurricanes." According to a study conducted at The Wind Engineering Research Center at Texas Tech University, concrete walls can withstand the 250 mph wind-speed conditions and debris present during hurricanes and tornadoes — far surpassing the durability of wood- and steel-framed houses.
Besides the comfortable tranquility that comes from living in a home built with removable/reusable forms, Safe Haven Homes are equipped with features that would dazzle any homeowner. Plumbing and electrical wiring are built within conduit inside the concrete walls, making them easily accessible for repairs later on. Friemoth also explained that each house is built with an "automatic bonus room" under the garage. It was this feature, stated Friemoth, that first attracted homeowners to Safe Haven Homes. "Wisconsin is hilly, with lots of walk-in basements, and people who ride motorcycles were excited about the idea of working on their bikes in the winter under the garage, where it was warm."
Safe Haven Homes, built with removable forms, will hopefully become a growing trend in the American building industry. They're safer, more economical, more comfortable and longer lasting than wood-frame homes. In concert with other concrete-building methods such as concrete masonry, ICFs, etc., homes built with removable forms provide another opportunity for the contemporary homeowner to enjoy innovation and comfort. Friemoth exclaimed, "I think everybody should be building concrete homes!"