Oak Ridge Laboratory Tests Soy-Based Spray Foam Insulation

By Steve Hudson | September 28, 2010

Each of the test structures included a main level and a finished basement. All four walls of the basement were insulated using BioBased 501. By partnering with Oak Ridge National Laboratory, Loudon County Habitat for Humanity is able to provide traditional-looking homes that are extremely energy efficient. The building industry as a whole benefits also due to the research findings that come out of these tests.

Effective building insulation pays long-term dividends, and a recent test conducted in Tennessee by Oak Ridge National Laboratory’s Buildings Technology Center evaluated the effectiveness of soy-based open cell spray insulation compared to that of traditional fiberglass insulation.

Oak Ridge National Laboratories was established in the early 1940s as an element of the Manhattan Project. Today, Oak Ridge looks at energy and environmental issues in a number of different fields.

The product being evaluated in the recent Oak Ridge test, BioBased 501, is a soy-based spray foam insulation manufactured by BioBased Insulation that is made even more environmentally friendly by its use of water (instead of HCFC or CFC) as a blowing agent.

Steve DeWeese owner of Endless Supply Company of Horse Shoe, N.C., and a BioBased Insulation Certified Dealer volunteered his time to travel to Loudon, Tenn., and insulate a Habitat for Humanity house. The United Soybean Board funded the test.

In the test, two 1,200-square-foot structures of comparable design were constructed by the Women Build Program of the Loudon County Habitat for Humanity in Loudon, Tenn. One of the structures was insulated using traditional fiberglass batts, while the other was insulated using BioBased 501, an open-cell spray polyurethane insulation.

To evaluate the performance of the insulation, each of the structures was tested using a blower door to measure how well the building’s shell or envelope prevents outside air from getting inside. This was measured using an index of "air changes per hour," or ACH, with lower ACH numbers indicating more effective sealing of the structure.

Once the foam is sprayed it is trimmed to create a flat surface in areas that will be covered by sheetrock.

Following the test, the ACH numbers for each of the structures were evaluated. The BioBased-insulated structure experienced 0.08 air changes per hour (ACH) at 4 pascals of pressure, while the fiberglass-insulated structure experienced 0.16 ACH under the same pressure conditions.

"The lower the number; the better the building envelope," said Jeff Christian, director of ORNL’s Buildings Technology Center.

ORNL also has worked with the local Habitat chapter to construct zero-energy homes using Structurally Insulated Panels made by sandwiching a core of rigid foam plastic insulation between two oriented strand boards (OSBs).

"In those homes, the rate of natural air changes ranges from 0.04 to 0.08 ACH, which is very good," Christian said. He added that the recent tests suggest that a "well-built" structure with an envelope of polyurethane foam insulation "can come close to a SIP-constructed home in air tightness."

For more information, visit www.biobased.net.