What’s the best way to repair this floor joist

beamrepair

Enroute to installing a new shower I find this giant hole cut out of the floor joist of the 1800's historic schoolhouse I call home.

Crazy thing is, the new shower placement…literally two inches over…makes more sense above ground and accommodates that pesky code rule that you actually have to be able to look down a drain and see the bottom of the p trap.

I'd hate to close up the floor if I could have done something to help repair that joist. I enjoy building things in general, but projects around this old schoolhouse are extra special. I get to see things like these old joists and imagine the builder that first put them there in the first place so long ago. Wondered if anyone may offer a solution to right this path.

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Best Answer

Considering you are probably putting the shower on top of this, you should definitely sister on a joist as large as is feasible. Be sure it runs as far as possible, hopefully to the bearing points (walls, etc.).

I am assuming the joist in question is the one at the bottom of the picture. If not, the advice should still apply.