You only need to be 1.25 inches away from the furring strip, the depth is a non issue.I'm leveling a crooked ceiling in a hallway in an old rowhome using 1x3 furring strips. As part of the project I would like to remove a ceiling fan/light combo and replace with three fixtures.
The three fixtures will be in a line centered directly over a stair railing and spaced about 12 inches apart. My question is regarding the wire I will run to connect the 3 ceiling boxes. Due to the location of the rafters it would be difficult to bury the wires behind the original substrate. Am I able to run the wires in the bay between the furring strips and the new ceiling? Or is this not enough depth to protect the wire?