Researchers at the Department of Energy’s Oak Ridge National Laboratory (ORNL) have developed a groundbreaking microwave radar technology capable of nondestructively detecting and measuring moisture inside building walls. This innovative tool has the potential to transform how homeowners and inspectors address moisture-related issues by enabling early detection and repair, thus preventing extensive damage and associated health risks.
Mold and moisture can wreak havoc on a home’s structural integrity and energy efficiency while posing serious health risks. Detecting moisture buildup early is crucial, and ORNL’s microwave radar reflection technology offers a solution that eliminates the need to remove drywall or cladding for inspections. The findings of this research were recently published in IEEE Xplore and presented at the IEEE Radar Conference 2024 in Denver.
"We know microwave radar shows great promise for this, because it's well known that it can measure the moisture in wood samples," said Philip Boudreaux, ORNL researcher. "But can it measure moisture in wood that is inside a wall to detect high-moisture issues before they become a big problem? That’s the challenge."
A Revolutionary Approach to Moisture Detection
The system uses microwave radar to emit signals that penetrate walls, reflect off materials, and return to the sensor. By analyzing the time taken for the microwaves to return, researchers can measure moisture levels in different wall layers. This technique not only identifies the presence of moisture but also maps its distribution within the wall’s structural sheathing, such as oriented strand board, a material commonly used in residential construction.
During proof-of-concept testing, researchers compared the radar’s moisture measurements with conventional handheld meters. "The results proved that microwave radar technology can detect and measure moisture within the sheathing and can do so within 3% when compared to conventional handheld detection meters," Boudreaux explained. The team also demonstrated that the radar could successfully detect moisture even with drywall placed in front of the sheathing.
From Laboratory to Real-World Application
The ORNL team has developed a portable prototype system designed for practical use by inspectors and homeowners. The miniature electronic device operates within a frequency range of 10–15 gigahertz and offers a lightweight, user-friendly design. "When developing the detector, we made a system specifically applicable to walls in residential homes and for general public access," Boudreaux said. "It’s small, portable, lightweight with easy setup and can be adapted to transmit within frequency regulations."
This portable radar system can also be used to inspect roofs and foundations, helping homebuyers identify hidden issues before purchase. Future research aims to expand the system’s capabilities to measure moisture in walls with various cladding materials, such as vinyl siding and brick.
Licensing and Future Potential
ORNL plans to license this technology to manufacturers, making it commercially available to the public. The widespread adoption of this tool could revolutionize building inspections by providing a fast, reliable, and non-invasive way to detect and address moisture issues before they escalate.
"With early detection, a small issue can be repaired before major damage occurs," Boudreaux said. "We've found what can help locate that moisture early, but we still have work to do and more materials to test and more boundaries to explore with microwave radar reflection."
This innovation underscores ORNL’s commitment to advancing technologies that promote safety, efficiency, and sustainability in residential and commercial construction.
Reference: https://techxplore.com/news/2024-12-nondestructive-microwave-radar-moisture-walls.html
