Rafter fire break distance

[AHI in AR]

I see very little attached housing -- it's just not common around here. You'll have to forgive me for being a little rusty on some of the fine points. This is new construction, and I seem to recall that the distance along the rafters (out from the common wall ) that the fire retardant material must span is 4'. However, I am not 100% sure that 4' is the correct distance. Assuming it is, as I see it, this is a 4' sheet, but without a continuous rafter or equivalent draft stop as a nailer, what we really have is a fire break of about 2' or so off the common wall. The end away from the common wall is drooping already and will likely fall off completely at some point if this is not addressed. Ignoring the obvious issue of the lack of fire retardant material around the water heater vent, am I correct that this needs work?

The small town muni inspector is known to be hostile to private home inspectors, so I'd prefer not to call him. Besides this, he missed some obvious issues during plan review and the framing inspection. I'm talking items as basic as no door or window whatsoever from the master bedroom for emergency egress!

Sorry for the grainy photo, I had to zoom all the way across a dark attic.

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