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I'm planning to do sister joist.

I'm planning to do sister joist due to some rot in my bathroom. Do I need to go from end to end or can I start them a Ft or so from the area that is affected? Does the area that is affected have to come out? The area that's is affected is not bad 3" along the top of joist maybe 1-2" deep.

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Posted 2014-02-03T06:22:42+0000  by i5h i5h

Hi i5h,


The first step is to determine why the old joist is rotting. Stopping the water leak or insect damage is a top priority.


Not solving the problem will result in more work later.


Installing a new joist using joist hangers is the best solution.


Place the new joist as close to the old one as possible, leaving some room to cut out the old one.


Apply construction adhesive to the top of the new joint where it meets the sub floor, this will help prevent squeaks.


Once the new joist is in place cut out the bad rotted joist and treat the area to prevent any further damage.


If you have to sister the joist start at least three feet on either side of the effected area.


Check carefully for insect damage or mold treat the rotted area before completing the repair.



Best Answer

Posted 2014-02-04T19:17:34+0000  by Mike_HD_OC
Thanks for the info. I've been reading up on how to do sister joist but I hadn't found info on how long they had to be n so on. Thanks again.
Posted 2014-02-04T22:57:58+0000  by i5h
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