I joist questions
mech644
| Posted in General Questions on
I’m replacing joists for a kitchen remodel. Installing 9.5” TJI230’s 12”oc spanning 15’, secured on each end with joist hangers fastened to double LVL girders. Three of the spans are doubled up where they pass under an island. Should those joists be fastened together, either at ends middle, both? If so I would fill inner web void with a piece of lvl planed to 1.5”, outer with 7/8” and then fasten thru with screws.
I couldn’t find anything in Weyerhaeuser documents that addressed doubling of I joists.
Subfloor is going to 3/4” T&G advantech glued and nailed.
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Replies
I-joists only need to be attached together if they are side loaded (ie stair opening), if it is just holding up extra weight, you don't need to do anything.
My suggestion would be to bump it up to the 3.5" flange ones and go for 16" OC. The wider spacing makes everything easier (ie tools fit, fans fit, ducts fit, standard insulation). Usually the cost delta between the two is not much.
Also make sure you plan out your HVAC ducting, sometimes you need a 2' chase to run a supply trunk, easy now, very hard later.
Thanks Akos. Weyerhaeuser doesn’t make the 9.5” depth joists in anything wider than the 230. Existing structure in the house made the 12” OC the easier path.