The Cook County Sheriff's Office said it had gotten approval from the state's attorney's office to request the warrant for the Northwest Side building where Gacy's mother once lived and where Gacy himself was employed as a maintenance man in the 1970s.
Gacy was convicted of murdering 33 boys and young men in the 70s and was executed in 1994.
The building had been searched in 1998 after a retired Chicago police detective said he had personally seen Gacy skulking around the premise with a shovel in the middle of the night, the Chicago Tribune said Sunday. The search turned up nothing pertinent.
"Speculation about this property has been out there for many, many years," sheriff's spokesman Frank Bilecki said. "This whole Gacy case has taken so many different twists and turns, (so) being able to close a chapter of it at this property would be nice."
The Chicago Sun-Times said the 1998 search was not considered to be in depth. The plan for the upcoming search will be quite thorough with deputies planning to bring in a ground-penetrating radar to look for signs of graves of other disturbances that might lead to new evidence or human remains.
"If anomalies occur, holes will be bored into the ground and samples taken for FBI cadaver dogs to sniff — before any more excavation is done," a source told the Sun-Times.