Originally Posted by
Chuck Jones
Have you ever seen plumbing vent pipes on the roof where the exposed painted portion has pushed up above the boot exposing unpainted pipe. This is likely related to exapnsion and contractin of framing and/or pipes.
My thoughts too.
Especially in Arizona where that time frame (5 am) would likely be the 'coolest' with the contraction peeking around then, followed by the next day's expansion due to the heat.
All it takes is one VTR (plumbing vent through the roof) to be rubbing against an undersized or off center hole in the roof sheathing and that pipe is going to be rubbing up and down, squeaking as it goes, with expansion and contraction. The loudest noise may be caused by the pipe, a fitting or coupling, getting 'hung up' on some tight framing, then, after sufficient contraction, the edge of that coupling or fitting 'pops over' the edge of the framing.
Either, or both, could be moving.