Universities play a pivotal role in research and development. In 2020, academic institutions spent $86.4 billion on R&D, according to the National Center for Science and Engineering Statistics. Some of those dollars – and the resulting projects – impacted materials, technologies,  applications and more in the composites industry.

This year’s annual feature article on university research highlights four composite-related projects, ranging from fundamental science examining defects in thermoset materials to envelope retrofits making homes more energy efficient.

Residential Retrofits Lead to Energy Efficiency

Project: Composite Panels for Envelope Retrofits

School: The University of Tennessee, Knoxville

Location: Knoxville, Tenn.

Principal Investigator: Uday Vaidya

The residential sector accounts for approximately 21% of total U.S. energy consumption, and the average household is responsible for releasing 70% more CO2 emissions than the average car, according to the U.S. Department of Energy. Researchers at the University of Tennessee, Knoxville (UTK) have developed a solution to help combat the problem.

“There is a strong need for dependable, cost-effective building envelope retrofit solutions in order to meet decarbonization targets,” says Uday Vaidya, Governor’s Chair in Advanced Composite Manufacturing at UTK-Oak Ridge National Laboratory. “We created a modular, overclad composite panel system that provides an innovative way to modernize buildings – and make them more energy efficient – without a lot of changes to the base structure.”

During the first phase of the project, UTK collaborated with Oak Ridge National Laboratory (ORNL) to develop the material solution. The team designed sandwich construction panels made from fiberglass, epoxy resin, polyurethane foam and pultruded profiles. The panels, which are five to six inches thick and measure either 4 x 12 feet or 5 x 12 feet, are fabricated using vacuum infusion and braiding techniques.

“They are very lightweight – less than four pounds per square foot – so they can be easily carried by two people and installed with small equipment,” says Vaidya. “The panels provide minimal disruption to existing structures, which is key. They are designed with all the necessary connections to homes and gutters for drainage.” The panels can also be customized to feature the desired finish, or wall cladding, such as siding, can be placed on top after installation.

UTK teamed up with the Building Technologies Research and Integration Center at ORNL for the second phase to identify homes for a demonstration project. Together, they selected 13 homes in the Knoxville area, each approximately 2,500 square feet, to receive a full-house envelope retrofit.