I see the Doubled FJ's under bearing walls with and with out a space between to allow plumbing sometimes.
Common: When Doubled FJ's are under a non-load bearing wall to eliminate the floor flex that creates a drywall crack above a door header on the wall above, typically between a bedroom and master bath.
Were only dealing with minimum codes, right?
north star, I asked my boss why and he said he's just always done it this way because once an engineer told him it was a good idea for walls that are parallel to the joists so they're not concentrating their load on one joist or even just the plywood subfloor if the wall falls between joists. It makes sense to me, I had just never heard of the idea until now and wondered how many architects and builders do it this way.& >
Also, ..."good practice" may not make good financial sense
in some markets.
IMO, ...if cost is not a concern, then Yes, Double FJ's make
good structural sense.
fj80, it may be that your "new" Residential firm cares
more about quality & integrity of their product than some
other firms.......Have you asked why this is considered
"best practice" at your new digs ?
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