The Northern Ireland U-19 regular has never played for The Owls but is regarded as a prospect for the future.
McArdle has made a few appearances in pre-season for Wednesday and impressed against Sheffield FC in an unfamiliar right-back position.
He will join up with former Owls striker Grant Holt at Moss Rose.
In other news, Sturrock has signed Manchester United's Chris Eagles on loan.
The winger would be a perfect short-term replacement for JP McGovern, who is out of contention until at least September with a back injury.
The 19-year-old will stay at Hillsborough until December 31.