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Replacing Improper Joist Sister

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A joist under my master bathroom that was notched about 40% on one end by a plumber at some point has been improperly sistered (sister cut too short--only 1.5' on either side of notch). I'd like to try and replace it with a pair of 2x10's cut to the full length, sandwiching the old joist in between and fastened with Gorilla Glue and 3/8" carriage bolts, as required by code here.

I managed to get all the screws and nails out of the old sister but I'm having trouble separating it from the joist as it was also glued with some kind of construction adhesive. Using chisels and a pry bar, I made some progress separating one end but fear this approach will take hours and be particularly difficult on the other end where its more obstructed by pipes.

Any suggestions? Is my approach overkill for a notched joist? No sagging or squeaking is present.

This is a 2x10 joist that runs 12' 4" across. My house is raised on pillars so I'm working in the crawlspace here.


Edited by Rob11232
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21 minutes ago, Marc said:

Heck, if it's that hard to pry off, I'd bolt it back.  At the most, I'd install another pier to support the longer end but probably wouldn't even do that, if it's holding alright.

I've thought about how I could leave it.  So, just add a single board on the other side and use longer bolts where this piece is?  I was under the impression a sister on either side was necessary. 

I assume adding another length on either end of the current sister would add virtually no strength since its not continuous and not resting on a beam on either side?

I have no way of knowing when the joist was originally notched but the botched repair was recent.

One other thing I've considered is using a metal strap on the original  joist but the notch is at the top unfortunately.

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