Fairbairn pulled a muscle while warming up for their preseason finale against the Buccaneers.
On Wednesday, the Texans announced they have placed Fairbairn on injured reserve.
They do not have to sign Slye to their 53-player roster. Instead, they can save the roster spot with a standard game-day elevation of Slye from the practice squad.
Slye played at Virginia Tech and has made 54 of 68 career field goals in the NFL, a 79.4 percentage with the Panthers.