The structure is so insignificant that Bartholomew County property records describe the address only as a vacant lot.
Riordan, who is senior pastor at Faith Lutheran Church on State Road 46 West, said he was concerned for years that someone would attempt to use the building for illicit purposes, he said.
The minister and businessman said his intent in purchasing the property had always been to clear the overgrown foliage to store boats and recreational vehicles for his Happy Happy Self-Storage company, located further south on Jonesville Road near the Bethel Village subdivision.
But after the small building's roof caved in about a year ago, Riordan decided the old house had to go. He agreed to allow the Mill Race Theatre Co. to remove the deteriorated siding to use in sets for last summer's production of "Oliver!"
It was only then, six years after Riordan purchased the property, that his discovery was made.
Once the old siding was removed, Riordan found that it had been masking a 20- by 26-foot log cabin for more than a hundred years.
After the minister received a $3,000 quote to tear down the cabin and remove the debris, Riordan said he was approached in January by Dennis Parman, owner of Peaceful Valley Construction northwest of Nashville. An inspection showed the hand-hewn logs with traditional saddle-notch style, as well as the former shape of the collapsed roof, likely dates back to the late 1830s to late 1840s, Parman said.
An expert brought in to assess the house confirmed its logs were made of chestnut, known for its resiliency against insect and water damage, Parman said.
The siding was likely placed on the cabin in the late 1880s to give it a more modern look, Riordan said.
But both he and Parman agreed the siding also was instrumental in preserving the integrity of the logs, he said.
"The wood is in remarkably good shape," Parman said. "This is going to make someone a beautiful home."
Such residences are extremely popular today, according to the National Association of Home Builders. While some people enjoy the historical value, others view these structures as a form of folk art, according to the association.
These cabins are especially popular in the rustic Nashville area, where the Brown County Log Cabins Tour attracts more than 2,000 visitors annually.
When reassembled with modern methods and techniques, historic log cabins also retain warmth better than drywall and are more energy efficient, according to the association.
Log homes are even touted as the "original Green House," as trees are a renewable resource in construction and less energy to manufacture, the association stated.
After Parman offered to clear the site in exchange for keeping the original logs — which originally was going to cost him Riordan $3,000, he accepted. While others might have sought additional financial gain in exchange for the logs, Riordan expressed no regrets about the no-money-involved agreement.
"I'm just really glad this historic home will be given a new life," Riordan said.
The dissembling of the cabin recently got underway after each of the logs was labeled, and should be completed by early April, Parman said.
Although his deal has not yet been finalized, Parman tentatively plans to reassemble the cabin for a client who recently purchased acreage along Albert Johnson Road, about six miles north of Gnaw Bone in Brown County.
Parman, who said he has more than 20 years' experience transforming antique barns and log cabins into new homes, expressed confidence that he can find matching logs for those that are not salvageable in Garden City.
If the deal goes through, construction of the new log home will likely begin in July, he said.