Recessed shower floor with i-joists
jandpp
| Posted in General Questions on
Not exactly a home efficiency question here but hoping some builder had done this before.
I’d like to drop the floor of my shower to make a curbless shower. The usual way to do this is to drop the subfloor so that it hangs between the floor joists flus with the top of the joists. I’ve seen this done with dimensional lumber joist but not with i-joists. Anyone done this? I was thinking of adding block as in the attached picture. Screw the side blocking together through the web and then the support blocking into both the side blocking and the side of the flange.
thanks for any advice
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Replies
I would extend the blocking the full depth of the I-joist web, so you're not putting extra stress on the web itself, but otherwise that seems like a solid plan.
For a curbless shower you also need to account for the depth of a mud pan or prefab system, so you'll need to drop the subfloor another couple of inches or so.
Take a look at the side load details (ie stair opening):
https://www.weyerhaeuser.com/application/files/2115/5907/2648/9030.pdf
The filler block has to be much larger but with at least a 1/8" gap. There is also a nail pattern to follow but I would also glue.