Best way to repair notched joist (with pic)

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I'm redoing my basement and came across a 2X8 joist that was notched at some point in the past.It is notched approx It is the last joist before the outside sill plate. As you can see it is close to the steel beam. What is the best way to repair it or strengthen it? I was thinking put another piece of 2X8 next to it, one end resting on the beam and extending a good 2 feet past the notch, fastening it with bolts and washers. Any inputs appreciated.
http://picasaweb.google.com/lh/photo/v6WX6ZtZwnFIjYv6yCXHVg?feat=directlink
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Your idea seems ok, you might want to raise the existing joist on the side away from the steel I-beam about 1/4 inch before connecting the parallel plate/joist as it will have a certain amount of "give"and by raising the existing joist, putting the plate in and then removing the raiser mechanism, the new pkate will have part of the load. Yoiu could raise the existing joist using a jackpost or even a 2x4 shoved under the joist at an angle and then moving the 2x4 to a more vertical position by hammering it toward vertical. A string and weight next to a ruler or even just a ruler can tell you when the existing joist is raised up the 1/4 inch.
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hr(bob) snipped-for-privacy@att.net wrote:

If you have a floor jack in your garage, you can use it and a 2x4 to take the load off the existing joist before you sister it.
I fixed a broken rafter that way once in a poorly-built shed. Had to jack up not only the broken rafter but the ones next to it to get the roof nice and even again.
Use nails and glue instead of bolts. A bolt thru a hole will have too much play even when you tighten it.
-Bob
Bob
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wrote:

joist, well slathered with glue, and using a 4X4 on a jack, or a jackpost (I would NEVER use a 2X4 on end for that kind of jacking). jack the joist up so it is inline with the rest of the joists and spike the 2X4 to the bottom with a row of spikes, spaced about 6" apart. You would be building a "spar" or "truss" as strong as the original beam by using the 2X4 as a "spar cap" in tension.
Whoever did that notch sure didn't have any concept of what they were doing!!!
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snipped-for-privacy@snyder.on.ca wrote:

Or use a piece of 1/4" steel flat bar to close up the bottom. Put some tension on the steel if you can. But even without tension, it would hold the joist together if it ever decides to break. And most importantly, it would *look* a lot safer than what you have now :-)
-Bob
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Whatever technique you use for attaching, scab or sister that joist on both sides, not just one side.
Sonny
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Why?
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wrote:

It won't twist.
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On Dec 31, 7:17pm, " snipped-for-privacy@att.bizzzzzzzzzzzz"

So I guess the assumption is that a new piece of 2 x 8, glued and screwed/lagged/bolted to one side would have enough strength to twist the existing joist if it should twist as it aged? I can see that, especially with the notch cut out.
How about if 2 layers of 3/4" ply were glued up and used on one side? That wouldn't twist would it?
Would that be stronger than a single piece of 3/4" on each side?
Just curious, that's all.
If 2 layers of 3/4" ply were used as the sister, glued and screwed
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Why sister both sides? (ideally)
It's a symmetry thing. The original un-notched beam was symmetric with respect to the vertical load it carried. Sistering only one side creates a non-symmetric joist. Probably a minor / second order effect but symmetry is ideal.
Adding 3/4" plywood to both sides of the joist restores symmetry to the system.
The chief engineer I worked with for nearly ten years taught me "God likes symmetry".
To repair the joist I would jack the notched beam slightly (to sister a member without relieving the load by jacking leaves the sister unloaded by the existing load). I would cut two sisters from 3/4" plywood, glue and mechanically fasten in place. As per other posts, the plywood should extend at least 18" beyond notch.
My choices of fasteners would be. 1) Senco M2 style staples; 2" o/c all directions, both sisters. 2) .148" dia plywood shorts; 3" o/c 3) Simpson SDS 1/4; 4" o/c
To get the sisters to take load you have to transfer shear from the notched beam to the sisters. That means jacking & good tight fastening (glue & staples, nails or lags). Bolts are typically installed with over sized holes, not the best way to transfer shear.
Keep the jack in place until the glue dries.
cheers Bob
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What is number 2?
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"Plywood shorts"
They are short nails designed for attaching plywood (normally 3/8" thru 1/2" thickness) to framing.
The theory being, no need to have a full length nail to attach plywood. They are really for shear walls but they will work even better in a static loading situation like this repair. The nails are just needed to transfer shear between the sisters and the damaged joist so no need to go crazy on the length.
The shorts are less likely to split the receiving member.
cheers Bob
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wrote:

I'm not a structural engineer, but I'd say no. Symmetry is your friend.

I don't believe two layers is twice as strong as one (fasteners, glue joint, etc.) Opposite sides would have twice the fasteners and glue. ...though I don't think the fasteners do much here.
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Maximum strength.
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On Dec 31, 11:52am, snipped-for-privacy@snyder.on.ca wrote:

They knew exactly what they were doing. They knew they didn't give a damn and wanted to be finished as quickly as possible.
R
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If you can....
Plan A---- run another joist the entire length and rest it on both ends at the same point the existing joist is resting. Basically you're replacing the existing joists load.
Plan B --- I would get a metal plate cut and drilled to span the gap, then bolt it to the existing joist.
Plan C ---- What you want to do. :-)
Caution... If you jack up the joist, be sure to check the floor above to see of any raising of the floor will effect anything. Sometimes raising only a fraction of an inch can make doors "out of plumb", therefore affecting their operation. Hank
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I have my kitchen floor above with ceramic tiles. Thats my only concern about jacking up the joist with tiles cracking, getting loose.
I can't run another full length joist, too many obstructions.
Rather than use bolts, can I use lag screws?
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I don't see why lag screws wouldn't work, just make sure you pre-drill the correct size hole.
I lagged some "modern-day" 2 x 4's to the 50 YO 2 x 4 studs in my garage for shelving. New wood to new wood was a breeze but I snapped the heads off a couple of lags using the same sized hole in the older wood. It was much, much harder and required a slightly larger hole.
I would also make sure there were some threads in both pieces of wood. I don't think that you would want all smooth shaft in either piece as the threads would hold everything in place better.
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Mikepier wrote:

Lag screws would be better than bolts. Bolts have a small, but significant, wobble-factor.
Don't forget to slather the sucker with about a quart of glue. Maybe some strapping...
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At a maximum inch and a half embedded the lag would not be nearly as strong as a bolt through a correctly sized hole. Not even remotely.
R
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