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One sagging floor joist

mitcholmes's picture

I'm working on an old one story bungalow house that has a problematic floor joist.  

The floor for the house is 2x8s, 24" OC, spanning about 12 ft.  The problem lies upstairs in the corner of the kitchen, where a large refrigerator sits. There is about a 2-3" sag in the floor, but only on one of the floor joists, which has also caused the doorway beside the fridge to be sloped.  Now most of the walls in the house have already been stripped, so cracking and stuff is no concern.  I should also mention that the owner of the house already has plans for the unfinished basement, and does not want any additional posts/beams added, since the ceiling of the basement is only about 80" anyway.  

my thought was to jack up the floor joist, sandwich a couple of joists to it, and since the basement is unfinished I can still access the foundation wall and mid beam where the original joists rest, basically making a new joist 3x the original size.  Think that's worth a shot?  

mitch (post #207322, reply #1 of 2)

Worth a shot?


Bevel the top of the joists you are going to install-it'll make it easier to roll them into position. 

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Yeah, sounds like something (post #207322, reply #2 of 2)

Yeah, sounds like something you should be able to "sister" fairly easily (though "fairly easily" is used in a relative sense), so long as there are no pipes or wires in the way.  Some people try to get full length joists in on each side, while others cut one or both ends a foot or so short and then through-bolt the ends to anchor them to the original.  Either approach can be made to work.

When you jack, don't forget to first plan how you'll work the "sisters" into place with the jack present.

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