On a 26-unit rough this morning, I failed three laundry boxes for missing listed hammer arrestors at the valve per IPC 604.9. Are you accepting arrestors back at the PEX manifold as equivalent, or requiring them at the quick-closing fixture supply to clear rough?
I’d install listed mini-resters ‘at the valve’; manifolds rarely satisfy 604.9. Your AHJ allow manifold calcs?
@jbarrett45 I only pass these with listed mini-resters at the laundry box valves; the one exception I’ve gotten was manifold-mounted AAs sized per the maker, manifold within their max run to the valve and behind a labeled access panel — submit that spec with your rough notes… Is your manifold that close and accessible?