Pensmore

General Information
Type:	Insulated concrete form
Architectural style:	Châteauesque
Location:	2700 Woods Fork Road, Highlandville, Missouri
Coordinates:	36°52' 47" N93° 12' 45"W
Construction started:	2008 - 2013
Governing body:	Private
Technical Details
Floor area:	72,215 square feet (6,709.0 m2)

Pensmore is a mansion under construction in the Ozark Mountains of Highlandville, Missouri. When completed, the home will be the private residence of Steven T. Huff and his family. It will be one of the largest private single-family residences in the United States. Huff is the chairman of TF Concrete Forming Systems, which is doing the concrete construction work for the home. Huff at one time worked in Army intelligence and was a CIA officer. Huff later founded Sensor Systems in 1993 and served as its CEO. The company, later known as Overwatch Systems, created leading commercial software products for medical, defense and intelligence applications.

Construction

Steven T. Huff Family LLC applied for a construction permit in 2008 to begin construction of the mansion. The home is unique, as it is an insulated concrete form structure that is designed to showcase sustainable construction techniques on a large scale. The home is designed to be earthquake resistant, bullet proof, blast proof, tornado resistant, bug resistant, and fire resistant. The home is capable of withstanding an EF5 tornado.

The home will approach net zero on heating and cooling. Pensmore will utilize thermal heat collectors, a geothermal ground source heat exchanger, radiant heating and cooling, advanced climate control software, rainwater collection, and helix steel fibers.

Huff chose the location in Missouri because the state offers a climate that has both warm and cold temperatures, which allows for better testing of the green technologies in the home. Additionally, the rural location in Highlandville was known for lack of construction regulation. The project is not subject to building regulations or building inspections, which would have complicated construction efforts.

Sustainability

A variety of exciting new technologies allow Pensmore to dramatically cut energy costs without sacrificing practicality.

Pensmore's heating system utilizes a cutting-edge technique for harvesting solar heat energy that exploits the vast energy storage potential of its steel reinforced TransForm concrete shell. Many builders already make use of traditional solar heat collectors, which are highly efficient at moderate temperatures. But until now, it has been expensive and impractical to "bank" the excess solar heat generated on sunnier days. Pensmore's newly-developed technologies enable it to store millions of BTUs of thermal energy while the sun shines, slowly releasing this "green" heat back into the interior at night and during cloudy days.

Secondary sources of heat include combustion of wood products grown on the estate (net carbon neutral) and "conventional" geothermal systems.

Similarly, Pensmore's cooling system will make use of a unique technology that is both innovative and practical. We will be releasing more detailed information on the heating, cooling, and air conditioning systems in the future, so check back for updates as the chateau approaches completion.

Sustainability means more than just energy efficiency. It also means minimizing total life-cycle costs through low and zero-maintenance materials, and reduced use of non-renewable products during construction. Perhaps one of the biggest environmental advantages of Pensmore is its inherent durability. Designed to endure for centuries, the chateau will leave a minimum impact on the environment while other structures are built, demolished and built again and again.

Pensmore relies on the following systems and technologies:

TransForm: super-insulated energy-storing concrete forming system
Solar thermal heat collectors
Geo-thermal
Radiant heating and cooling
Advanced climate control software
Rainwater collection
Helix steel fibers

Pensmore is particularly noteworthy for its exceptional structural integrity. A proprietary TransForm concrete shell is reinforced with a special blend of Helix steel fibers by PolyTorx, making it highly resistant to extreme disaster conditions-including tornados, earthquakes, and even blasts. We believe these structural features will find application in some of the most turbulent regions of the world, where builders face unique challenges.

TransForm: TransForm is the next generation of insulated concrete form (ICF) technology developed by TF Concrete Forming Systems. Its versatility enables a builder to take virtually any architectural design and implement it with superinsulated concrete, optimally placing the insulation to take maximum advantage of the thermal mass effect. While several ICF systems exist on the market, many have steep learning curves, result in warped or out of true walls, and are prone to "blowing out" unpredictably on the job site as the concrete is poured into the forms. TransForm's patented design is simple for contractors to learn and use, and boasts new features that have virtually eliminated the "blow out" problem. Finally, the system is versatile enough to accommodate the complicated jogs and angles of Pensmore's French chateau design. TransForm allows even the most sophisticated architectural styles to be molded out of reinforced superinsulated concrete.

Helix: As a building material, concrete is extremely resistant to compressive forces. Still, most concrete structures need to be reinforced with special bars, grids, plates, or fibers for added tensile strength-particularly in high-stress environments. Pensmore™ accomplishes this with Helix steel fibers by PolyTorx: a reinforcement technology originally developed at the University of Michigan for earthquake and blast resistance in situations where rebar would simply not be enough.

As concrete is stressed or bent, rebar and ordinary fibers begin to fail after frictional pull out. But Helix fibers feature a unique "twist" shape that increases the frictional resistance-much like trying to pull a corkscrew from a cork without untwisting it. More importantly, the "twist" shape changes the failure mechanism from friction to a torsional mode. The additional force required is so large that the result is a performance level never before possible. This makes our structure more resistant to extreme weather and disaster conditions, allowing its concrete walls to absorb shocks and bend with them instead of breaking away from the steel rebar that reinforces it.

Concrete is one of the strongest and most durable known building materials in the world. Many Roman concrete structures built over two thousand years ago are still standing. By applying state-of-the-art technology to an ancient building material, Pensmore™ takes concrete building to the next level.

Building Pensmore

Comfort Design Inc. collaborates with Pensmore™ on its unique HVAC system.

Select individuals and companies have come together in collaboration to bring this living laboratory to life. On this page you will find information about these individuals and companies, and the roles they play in building Pensmore.

Core Technologies

TF Forming Systems developed and manufactures the TransForm super-insulating energy storing concrete forming system that is used to form the structural components of Pensmore. TransForm results in very straight and true walls of incredible strength.

Helix: The TF forming system can utilize any type of concrete and reinforcement. For Pensmore we use a combination of conventional steel rebar and Helix, a unique ultra-high performance steel fiber from Polytorx. Helix reinforces in all directions and makes the concrete much stronger and more elastic.

Andersen Corporation is the selected manufacturer of windows and doors for Pensmore. The developers chose products with Stormwatch® protection and SmartSun™. Specifically designed for coastal applications, windows with Stormwatch® provide added weather and security protection 24/7. SmartSun™ blocks 95 percent of UV light, which can be instrumental in reducing energy consumption and reduce fading of interiors. This combination provides a window and door solution that is both disaster resistant and energy efficient.

Meek's The Builder's Choice is Pensmore's preferred source for building materials. We turn to Meek's to supply Andersen windows, roof LVLs, shingles, and more because of the personal attention they provide. We also utilize the unique tools at their one-of-a-kind design center.

City Wide Concrete is the Ready Mix plant that supplied the concrete for our TransForm walls. City Wide adds Helix steel fibers at the plant. Superplasticizers allow a very strong but highly pumpable mix.

Vulcraft supplied the steel joists and pan used to support the concrete deck floors of Pensmore.
Deville Steel supplied rebar and various steel components including beams and bearing plates.