Fire-Protected Floor Over Crawlspace
Change is hard!
I designed a ducted mini-split system for a new 1,800sf all electric home in the Southern California desert. The permit plan reviewer is requiring the floor to be fire protected per CRC R 302.13. because the ducted mini-split air handler and ductwork is located in the sealed non-vented crawlspace.
Floor fire protection requires either 1/2″ gypsum wall board or 5/8″ wood structural panel membrane applied to the underside of the floor framing members. The code makes this requirement for floor assemblies located directly over a crawlspace for the installation of “fuel-fired or electric-powered heating appliances”.
I believe mini-split air handlers don’t fall into that category but can’t find the supporting code language. No backup resistance heat coils are specified.
The loads are: sens. 17,871, lat. 897, tot. 18,769, shr 0.94, outside design temp is 109F.
I prefer to use Fujitsu’s vertically mountable ARU18RLF in a wall closet but wasn’t able to bring the cooling loads into it’s operating range.
I ended up specifying Mitsubishi’s PEAD-A24 that has to be mounted horizontally.
Locating the air handler in the crawlspace it not my first choice but the house has no attic or dropped ceilings.
Has anybody run into this code issue or am I missing something?
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