A limestone foundation supports the Dodge County Courthouse, the oldest continuously operating courthouse in Minnesota. The limestone blocks and mortar in the older portion of the building were installed more than 150 years ago. County Maintenance Director Duke Harbaugh has spent countless hours working on how to save the old foundation from the corrosion caused by rising damp.
Even though the building sits on a hill, ground water and dissolved salts migrate into the basement through capillary action and literally dissolve the mortar between the limestone blocks.
In years past, workers tried painting and plastering over the deteriorating walls, but the moisture and salts continued their slow destruction of the foundation.
Then, almost magically, Mr. Harbaugh learned of a solution to this inevitable decline. A company called RenoDry can install devices in the basement that “…change ambient energy so it influences the water molecules to release themselves from the masonry and either evaporate into the air of the basement, or gravity pulls the water and dissolved salts back down and out of the walls. As long as the system remains in place in the building, rising damp will not come back. The walls will dry out and the deterioration will be halted,” explained RenoDry’s CEO Don Brown.
“It’s like two magnets attracted to each other,” explained Michael Clancy, Chief Technology Officer for the company. “We basically reverse the polarity of the magnets - if you will - and they now repel each other. The water molecules and the masonry separate where before they were held together.”
Brown and Clancy installed two of the devices in the courthouse basement in early June. In just a few months, the results will become noticeable, they explained.
The technology has been in use for the past 30 years in the United Kingdom and is now available in the U.S. The company’s U.S. headquarters is in Kansas.
In 2020, devices were installed in a county building in Waseca and staff members there have been very pleased with the result, said Mr. Harbaugh. Results are guaranteed, said Clancy.
When the deterioration is stopped, repairs to the old walls can be completed and the repairs will last.The county commissioners approved the installation at their first June meeting and the group will be updated with the results.