After listening to testimony on Feb. 11, April 14 and Wednesday, McDowell said he found DeLauter's explanation of the fire incredible.
The judge said DeLauter's statements that he was going to pay for all the work with a large number of already "maxed-out'' credit cards also was unbelievable.
"I believe you are a good person who found himself in an impossible situation,'' McDowell said, alluding to the 45 days DeLauter had to remove the building from National Park Service property.
McDowell originally sentenced DeLauter to 10 years in prison for the crime of first-degree arson but suspended all but the 10 months to be served in the Washington County Detention Center.
Restitution to a half dozen fire companies was set at $5,163, plus a $1,500 fine and $525 court costs to be paid within the first 18 months of the three years probation, McDowell said.
Damage to the structure at 18100 E. Main St., Sharpsburg, that formerly housed the maintenance department of the Chesapeake and Ohio Canal National Historical Park was set at $150,000.
At the time of the fire, DeLauter told investigators he had taken out an insurance policy on the building April 23 with Quality First Insurance Co., where he said he was employed.
An investigation revealed DeLauter didn't have insurance on the building at the time of the fire, according to testimony.
DeLauter had finalized the contract to buy the cabin for $5,000 from the National Park Service on April 8, court records said.
He was awarded the bid after the park service sought a buyer who would move the building, court records said.
The log building was built in the 1960s and did not fit in with the historic Antietam Battlefield, according to former battlefield superintendent Susan Moore.
National Park Service officials had planned to turn the area into a parking lot for visitors to Antietam National Cemetery, she said.
DeLauter testified he was sleeping in the basement of the building on April 24 when he awoke and saw fire in the floor above him.