Local construction company builds energy-efficient homes

In the late 1940s in post World War II America, the federal government began developing a panelized system of building, a method that is still utilized as "one of the most energy-efficient on the market today," according to Dennis Culpen, owner of DC Construction in Boaz.

Culpen, who has been involved in the building industry for about 26 years, has been constructing nothing but panel system homes for the last 24 years. He has built 193 houses within a 60-mile radius of Springfield, with values ranging from $85,000 to $600,000. He also has built panel homes in Oklahoma, Louisiana, North Carolina, South Carolina and Georgia.

Culpen said he is seeing increasing interest in his energy-efficient panelized system homes. He gets three to five inquiries a week on his homes, and said he has a one-year waiting list.

Building with panels

Culpen has been an Insulspan dealer since the early 1970s, using structural insulated panel systems, or SIPS, for construction. This system comprises panels of polystyrene laminated between two pieces of oriented strand board. These panels are used in the exterior walls and roofs of his houses.

Culpen utilizes post-and-beam construction with these panels, a method that is "one of the strongest and most energy efficient on the market today." Compared to a stick frame house, the panelized home is twice as strong and able to withstand winds of more than 200 miles per hour, Culpen said.

Panel system construction provides superior insulation to traditional fiberglass, which compresses over time, according to Culpen. Also, panel-system walls are straight even a very long wall with siding will not have visible variations or ripples.

Culpen feels the panel system is superior because it eliminates dependency on wood, particularly wood from older forests. The wood used in panel system homes is grown specifically for building and printing. No older forests are touched.

His type of construction also doesn't require as many headers over windows and doors, or as many studs in the walls because the panels can be placed on larger centers, he said. They "use one-third less wood on our outside diagram than a conventional stick house," said Culpen.

In terms of up-front cost, Culpen said the cost of panel-system construction is comparable to that for conventional stick frame homes.

"I've been building houses in this area for about $65 to $75 per square foot," he said, which is about the going rate for a stick frame home. However, the cost can run as much as 5 percent higher than for traditional construction.

Energy issues

According to Culpen, panelized homes are 70 percent to 80 percent more energy-efficient than conventional stick frame homes.

Lower energy usage translates to lower energy costs. Culpen said his experience with his own panel-system home indicates a 50 percent savings, "but I have people tell me they have 80 percent savings."

These homes cool better than they heat because of the density of the air, said Culpen. And there is more opportunity for savings in cooling than heating in this area of Missouri because of the hotter summers, Culpen said.

Panel-system homes are 15 times more airtight than conventional stick frame homes, Culpen said. "We don't use Tyvec much because we don't have air filtration." There are no drafts, because it's all sealed off in a panel house, he added.

In addition, the panelized system home meets all government building qualifications, satisfying all regulations. The panels are also nontoxic.