Affordable Home in Tulsa Able to Withstand Tornado-Force Winds

An affordable, energy-efficient demonstration home in Tulsa, OK, that has been built to withstand tornadoes could serve as a model for new construction as the city seeks to replace its stock of 6,300 sub-standard houses for moderate- to low-income families, according to PATH News, a publication of the Partnership for Advancing Technology in Housing.

The Millennium House was built by Don McCarthy, an 81-year-old retired engineer, with assistance from Neighbor to Neighbor, a non-profit umbrella organization.

Completed this summer, the 1,200-square-foot house was built on a concrete slab and uses cutting-edge technology and structural innovations to provide shelter that is durable, inexpensive to operate and extremely healthy. Among the home’s innovative features:

• Twelve-inch Insulated Concrete Form (ICF) walls — constructed with stacked, high-density Styrofoam block and filled with concrete — provide an R-factor greater than 30. With energy-efficient windows and the planned addition of R-40 insulation in the ceiling, the house will exceed ENERGY STAR® specifications.
  
• Conferring with the American Lung Association, McCarthy installed a 120-CFM ventilation unit to replace the interior air every few hours. An energy recovery unit and filtration unit were incorporated into the ductwork. There is also no carpeting in the home and no foundation plantings within 10 feet, earning it a “Health House” designation.
  
• Relying on expertise from the Mechanical Contractors Association of Eastern Oklahoma, two 200-foot wells were drilled in the backyard to accommodate a geo-source unit. Along with the ICF walls and state-of-the-art HVAC equipment, the home’s utility costs run less than $20 a month.
  
• The home’s walls are tied to the concrete slab and footings with No. 4 rebar and four-foot centers and roof trusses are secured to the walls with hurricane straps so that the structure can withstand an F3 tornado and winds as high as 205 miles per hour. The home also features a safe room built to withstand F5 tornadoes, which can generate winds of more than 260 mph.

To make the home more fire retardant, McCarthy chose electric over gas and used nonflammable materials that — in addition to the ICF walls — included steel studs and an ancillary steel framework.

McCarthy estimated that the price tag of the finished home will be about $62,000 — some $45,000 under market value, thanks to support from non-profit funds and volunteers and also because it was built on an inexpensive lot.

Researchers from the University of Tulsa and the American Lung Association have been conducting tests on the home’s performance. [ return to top ]