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Poor mans joist hanger 2

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SocklessJ

Structural
Aug 24, 2017
45
I recently had my deck rebuilt, and the contractor used 2x2 ledger strips instead of hangers to support the joists (2x10s @16”, 14’ span). To my surprise, my jurisdiction still allows this inferior detail. After spending so much money, I hoped for something truly robust and was wondering what I could do to beef it up.

Adding angle brackets, such as simpson A35s, would risk splitting the joists, which have (4) .120” toenails to the ledger. So instead i plan to connect each joist to the ledger with a 6” long piece of 2x2 and construction adhesive. You can get 800psi out of loctite PL, so we’re talking 2.4 kips with a safety factor of 3 . If I orient the grain properly, I should be able to prevent shear parallel to the grain.

Does anyone see any issues with this fix? I know the adhesive isn’t very ductile, but does that really matter for shear? I rarely do any wood design, but Id imagine these adhesives being very useful in retrofit situations.
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Not sure why you would think nailing in the A35 angle would split the joists. Yours is exactly the application they are made for.
 
You can simply install joist hangers. Just take a Fein tool or sawzall and increase the gap between the joist bottom and the ledger to gain room for the hanger seat. Sometimes you can just beat the hanger in without doing anything.
 
I would use an angle that is rated to support the end reaction of each joist.

I would conservatively assume the capacity of the toenails and ledger strip connection is zero. Toe nailed connections are rarely used for this type of application because the strength is highly dependent on the angle of the nail and penetration into the ledger, which are easy to get wrong on the job site. Even if the toe nails were installed perfectly, I'm not sure that you'd have enough capacity with (4) 0.120" nails.

While I don't know the specifics of the ledger strip detail, if I'm imagining the detail correctly, using such a connection is also not ideal, because it transfers the load from the joists to the ledger below the neutral axis, which makes the bottom of the ledger prone to split and potentially break off. The wood design code discourages such connections.

Finally, I would not use glue for this. In terms of on-site construction, glues are never used (in my experience) for structural connections, aside from providing extra restraint against movement, like floor sheathing glued (and nailed) to interior floor joists. In general, glues are only used in controlled factory settings (like in constructing Glu-lam beams). I would doubt that the glue will hold, considering potential temperature differentials between the joists and ledger as well as the normal tendency for wood to shrink and swell, which I doubt the glue can accommodate.
 
The solution by XR250 is probably the best option if you're able to get the joist hangers in there.
 
XR250,
The joists are all notched, so there's no way I could get a hanger in without cutting out the ledger entirely.

Bridgesmith,
You don't think putting (10) nails in the end of a notched 2x10 is too much? I guess I could make a mock-up and see what happens.
 
They have a few different framing angles - a smaller one may do since you're just reinforcing the connection. While the detail is sub-optimal, it's in there for a reason: it works if done properly. It's not as resilient and won't last as long, so you really just need to add that resiliency and longevity. An A34 would probably work - go stainless if you're worried about corrosion. Use the SD screws rather than nails. That will go a long way to prevent splitting.
 
SocklessJ said:
XR250,
The joists are all notched, so there's no way I could get a hanger in without cutting out the ledger entirely

Ahh, they did it the real shitty way. Most times, the band is one size bigger so they don't have to notch.
You can also cut out the ledger on each side of the joist to add the hangers (leave the chunk under the joist)
 
I didn't realize it was notched. You would probably use angles sized for the remaining depth of the notched joist. The shear capacity of the joist is also reduced, so if you use angles sized for a 2x8, which is what you effectively have, you should be able to match the capacity of the notched joist, using the nails the angle would typically have for a 2x8.

The best solution, I think, would be to temporarily support the joists, remove the ledger strips, and install joist hangers.
 
Progressively saw the ledger out at each joist and install joist hangers -

Palm nailers work well for tight quarters nailing - can probably rent one and a compressor ...
 
Use a multitool to slot around the ledger, then bash in the hanger.
 
SocklessJ said: "The joists are all notched, so there's no way I could get a hanger in without cutting out the ledger entirely."

If you add a hanger, then the 2X2 is no longer needed.

What comes to mind for me (given my current job) is a Simpson HUS26 hanger. It has a longer seat than lighter joist hangers, so the missing notch wouldn't matter.

Any truss plant will have them or a similar hanger in stock.

Edited to add - They make 1 3/8" and 2 7/8" screws that can replace the nails in hangers. I can't think of the brand name offhand. They might be a good choice for installing hangers in a tight spot.
 
BridgeSmith said:
he best solution, I think, would be to temporarily support the joists

Not needed as the toenails will hold the joists. Honestly, in my experience, the ledger does very little as I can physically rotate most of them by hand. The toenails are doing the real work.
 
The toenails are doing the real work.

That would make me nervous; toenails don't offer much shear capacity, especially with the haphazard installation I usually see. Of course a nailed-on 2x2 ledger isn't much of a support, either.
 
Could you add blocking matching the depth of the 2x2 and attach the hangers to that? Would also allow you to support the joist outside the notch.
 
XR250 said:
You can also cut out the ledger on each side of the joist to add the hangers (leave the chunk under the joist)

I think this may be the simplest and best solution.
 
Just another thought:

Joist hangers are quicker to rust. I just replaced a (god knows how old) set of stairs at my exterior deck where the fasteners and hangers were so rusted-through that most of them just pulled out. Very dangerous. I replaced the stringer supports with nailed 2x2 ledgers. If your deck is exposed to the elements, I'd recommend some caution here.

Now granted, your case isn't identical, but if the 2x2 ledger is designed to properly resist the joist loading, I'd add an A35 to one side of each joist to help with the vertical load and provide a bit of lateral restraint as well and call it a day. Make sure you use galvanized nails.
 
You can buy stainless hangers. Also, yours may not have been z-maz coated - like the current stuff.
 
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