Chateau Pensmore being built to last

It's hard to imagine a private residence raising as much speculation as Chateau Pensmore.

As travelers along U.S. 65 have watched the estimated 72,000-square-foot mansion rise on a mountaintop near Highlandville, curiosity has risen with it.

Owner and visionary Steven T. Huff says he's heard just about every conspiracy theory out there, including it being a fortress for the "illuminati" in case of a third world war or Armageddon, connected by underground tunnels to major cities throughout the U.S. Huff laughs at this one. "Really. Tunnels from L.A. Where would I put the dirt?" he asks pragmatically.

And while it is true Pensmore is larger than the White House (which is about 55,000 square feet) and being built in the grand style of a French Chateau, it is being built for solidly pragmatic reasons.

Huff says he had essentially three goals when he started planning the home in 2005: to create an energy-efficient home that is disaster resistant and to build a home that will last his family for generations to come.

To accomplish those goals, Huff is designing — yes, it's still very much a work in progress — the home with the latest technologies. The walls, floors and nearly all of the decorative details are created by using an insulated concrete form system developed by TF Forming Systems. And the home is heated and cooled through a combination of geothermal and solar sources, which are maximized by the insulation of the walls.

The concrete walls are a foot thick and have 4 inches of foam insulation on the exterior and 3/ 4 of an inch insulation on the interior. And the entire exterior is being clad in stones manufactured on site. "We spent a lot of time developing a stone mix impermeable to water," Huff says.

Huff says he first experimented with the TF system while working on a project at his home in Virginia.

A tornado had struck down the road from him. "I was getting ready to build a barn, so I thought I'd see if I could make it … energy efficient and disaster resistant," he says.

"I bought my first TF product and did a fairly extensive testing of it," Huff says.

Huff became such a believer in the product's potential, the computer software entrepreneur and physicist bought into the company and become chairman and director of engineering of TF Forming Systems.

Huff says the durability of the product in large part stems from the introduction of Helix wire. Thin, twisted strands of high-tensile wire are mixed into the aggregate used to form walls and other features. Huff says these wires change the physical behavior of concrete, making it much stronger and less vulnerable to impact, high winds and even explosive blasts. Walls blasted by high winds and battered by debris, for example, would bend rather than break and flex back into place.

As Huff leads a tour of the nearly complete guest wing — which includes five guest suites complete with kitchens — and shows how the mechanics of the house actually work, it becomes clear this project is about far more to him than just creating a lasting home for his family.

For Huff, the project is as much or more so about the science discovered along the way as it is about the completed house. "I wanted to build something large enough that it would be a lab-scale building," he says.

He's invited students studying physics and engineering from his alma mater, Hampden-Sydney College, along with others to study how the house works and how to improve its efficiency. Students from Drury University and College of the Ozarks also have studied the home.

"It's a good project for them because it's real," he says.

Another reason for the home's scale is to show how the TF and Helix technology can be used in larger commercial applications, such as hospitals, schools, nursing homes and other buildings used by the public. "Trying to evacuate a hospital in a tornado is not a good idea," Huff points out.

While Huff is most keen to discuss the technology and astounding energy efficiency the guest wing has shown in its first full year of operation (93 percent), he also takes time to note some of the details of the home.

A descendant of the original Liberty Tree is planted in a place of pride on the 600-acre property. A section of the guest wing includes a play area, children's library and a large stage for his granddaughter.

His daughter, he says, is in charge of decorating the home, which Huff says he hasn't much interest in. "And if I did, they wouldn't let me," he says.

Other features of the home include a great room with a 32-foot ceiling, more than a dozen bedrooms and bathrooms, three elevators, an observatory, massive library, a 40-foot by 60-foot kitchen and so much more.

The main portion of the house, however, is still very much a work in progress. Huff wants to take the data he's collected on the guesthouse and use it to make further improvements in the energy efficiency of the main house.

"Now it's not just theory," Huff says. "We know it works."

When asked if he knows how long it will take to complete Pensmore, Huff estimates about a year and a half, then hedges his bet.

"I have a place to live, so the short answer is, no. It depends on where the science goes," he says.