When money isn't an issue, you can build anything you want with concrete.
Contractors who build development or “tract” homes are concerned about the productivity that results from installing the same design and repeating the same procedures over and over again. Selling at the right price is central to this building method as well. In contrast, the emphasis for custom homes is the structure's uniqueness. As a contractor, you aren't trying to achieve maximum efficiency or the least cost; the trade-off is between architectural elements and cost. These homes usually are built for owners, who often become involved in the design process and the construction details. But some homes are built on speculation too.
Building concrete homes requires a level of commitment on the part of the builder because there is a learning curve. When trades work on their first concrete home project, they tend to be nervous about how their profits will turn out. Contract proposals tend to overprotect them in terms of price. But strong loyalties for concrete home construction develop as well. Builders often specialize in concrete construction and preach the values over all other building systems.
WHY PEOPLE BUY CONCRETE HOMESJason Fritz, an insulating concrete forms (ICF) specialist for Cemstone, Mendota Heights, Minn., says that word of mouth is the primary way that people learn about concrete houses in his area, either through someone else or knowing someone who lives in one. He says energy efficiency is the number one reason for interest, followed by quietness and comfort.
In some parts of the country, safety from weather events is the primary reason for building concrete homes. Building codes in Florida, for instance, now require that homes withstand sustained winds of 146 miles per hour. You can build a wood house to manage these wind shears but with concrete it's much easier. For that reason, plus mold, rot, and termite protection, approximately 80% of home construction in Florida uses concrete.
 Left: Using removable form construction, Security Homes builds a concrete home on a 12-foot pedestal to resist hurricane winds and floods. The 3400-square-foot home focuses on local architectural detail.
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Building along coastlines in known hurricane areas requires extraordinary means, but for people with financial resources who want ocean views, concrete custom home construction is the primary choice.
Mold resistance is an important issue for builders. Higher energy prices require that homes have a tighter seal, which results in trapping moisture inside walls and living spaces. With higher humidity, mold and fungus feed on cellulose—the primary ingredient of wood and paper. But there is no food source in concrete. Builders are sensitive especially to mold issues because they often get stuck with the complaints and the remediation.
A HOME IN THE BAYOUDave Pfanmiller, managing partner of the Security Building Group, Gulfport, Miss., specializes in building concrete homes in coastal regions. Their current home under construction is in Gulfport, Miss. The owners, whose previous home was destroyed in Hurricane Katrina, wanted to rebuild at the same location because of the beauty of the Bayou Bernard area—a short distance from the “back bay of Biloxi” and the Gulf of Mexico. The owners' children have grown up so they weren't interested in a large home. “This one will only be 3400 square feet but cost over $1 million. Not large by custom home standards, but the owners were more interested in architectural detail than gross footage and the home we are building is fascinating,” Pfanmiller says. They chose concrete because they wanted maximum storm resistance and strength, with energy efficiency as a second criterion. The first floor is twice the area of the second floor.
 Above: Precision aluminum forming systems are used to cast exterior, interior (load bearing), and ceilings at one time. Photos: Security Homes
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To avoid the destruction by another hurricane, the house is being built on a platform 13 feet off the ground. Treated timber pilings were driven to a 45-foot depth, through 25 feet of organic materials and sand after that. Pfanmiller says that the pilings depend on skin friction to support the loads along with heavy-concrete grade beams connecting them at ground level. Concrete columns measuring 12x24 inches and 12 feet long rest on the grade beams with an 8-inch-thick concrete deck attached to the top of the columns to provide the rigid elevated platform for the home.
Pfanmiller's company builds walls with a removable form building system. A high-precision aluminum forming system provides very flat wall surfaces that can become the finished surface—no drywall needed. Expanded foam insulation can be placed on the outside, inside, or in the middle. The system allows for the construction of exterior or interior walls and decks (ceilings) with unsupported spans as long as 20 feet on a 6-inch slab; longer spans can be incorporated with a thicker slab or a concrete ribbed floor system. For this home, the exterior walls, primary interior walls, and decks are concrete. The roof of the structure is wood-frame construction with strong connections to the walls creating a load path to the pilings. A standing seam steel roof completes the structure.
Pfanmiller says his company is willing to create any architectural detail that an owner wants. There are no real restrictions for using concrete. But for removable form systems, it's best for floor plans to be designed in 4-inch, 8-inch, or 1-foot increments.
