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GC/carpenter
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IF holddowns back to house floor joists are required for permit,
and IF the house joists run parallel to your deck joists
and IF the ceiling below is finished,

here's a solution... requiring zero drywall work.

dproc, the bracket bs is strictly for retrofit applications. Straps would do an excellent job of locking the ledger down during framing stage, but that only works for new construction projects. And there's no easy way to replace the ledger after 30 years, not without cutting the straps and installing the new ledger differently.

Mac













Damn, the pics aren't opening for me. I really wanted to see that your solution too.
 

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Mac
I like that solution, but you cut the rim joist without repair. Or did I miss something?

My understanding of the need for lateral attachment: the live load of people at the edge of the deck.
 

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Talking Head
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Which is why I'm soooooo happy that they make me do this crap in Rhode Island. Ya know, because we have so many earthquakes....

Thanks for the pics, by the way, Mac. That's a much better solution than my hole saw idea. Around here they're happy with the DTT2 connectors, which is kind of sad but I don't complain because it's all unnecessary anyway.
 

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Mac
I like that solution, but you cut the rim joist without repair. Or did I miss something?
I didn't post up all the pics of the sequence because every situation would be different. I wanted to give folks "food for thought" on one possible solution for hold down requirements.

Yes, if you open up the house rim, you'd need to put humpty back together. Here's the pics showing how I buttoned up the house. Note that I didn't cut the house rim completely - I left solid meat at the top and only cut a hole big enough to get my hand and a palm nailer inside. In this particular situation, the house joists cantilevered beyond the top plate by a foot or so, normally you'd have that top plate of the wall below to screw into as well.

Ethan, DTT2Z's would work in this situation as well. The new low profile impact drills are small enough to get into a hole that size. Honestly, this was a project I built 6-8 years ago and I don't remember why I used those particular hold downs. Maybe that's what was in stock at my lumberyard, maybe I had 'em laying around my shop from another project...who knows!

Mac


Plywood scab screwed to existing house rim on right and top sides


Chunk of 2x screwed to plywood scab on right and top sides, screwed to 2x block on left side


Chunk of ply flushes out house sheathing
 

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Talking Head
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I thought those were the correct hold downs for the lateral application. The DTT2 is really just tie rims/posts to joists. If you used enough of them I'm sure you could achieve the right specs but two per deck aren't likely to add much.

I've attached them with Simpson SD structural screws using either my cordless right-angle Bosch or a regular drill with a 12" extension going to a right angle extension if it was REALLY tight. Those screws are pretty awesome for sneaking a bracket in.
 

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I thought those were the correct hold downs for the lateral application. The DTT2 is really just tie rims/posts to joists. If you used enough of them I'm sure you could achieve the right specs but two per deck aren't likely to add much.

I've attached them with Simpson SD structural screws using either my cordless right-angle Bosch or a regular drill with a 12" extension going to a right angle extension if it was REALLY tight. Those screws are pretty awesome for sneaking a bracket in.
I think the DTT2 is designed for securing railing posts more so then the ledger
 

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I think the DTT2 is designed for securing railing posts more so then the ledger
It's used for that and also for the deck to house when they're used back to back like the detail Andy/Scipio posted on the first page of the thread.

On the other one shown where it's attached to the 2x4 that's scabbed onto the joist the problem with that one structurally is it's only as strong as the nails that are holding the scabbed on piece of wood to the joist so it's very unlikely that it has the required 1800+ pounds of tension loading that is required.
 

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Talking Head
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Ok, so I think both Cali and Rio are agreeing with me....

My point is that many of the AHJ's that I deal with only require 2 lateral hold downs and I don't believe that two of the DTT2's will provide sufficient lateral support for more than a very small deck. It's not really an issue for me as we have virtually zero seismic activity but I think an engineer could figure it out pretty quickly. A call to Simpson could probably get the answer in a hurry too as I'm sure they have done all this math before they started horning it into the code books.:rolleyes:
 

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the problem with that one structurally is it's only as strong as the nails that are holding the scabbed on piece of wood to the joist so it's very unlikely that it has the required 1800+ pounds of tension loading that is required.
I was using 16d 3 1/4" nails in the holes of the holddown. The 2x4 scab was so the nails wouldn't punch through the side of the house as I was attaching holddown to the end joist. All nails go through hold down, 2x4 scab and 2x8 house joist.

And I've had engineers spec DTT2Zs in that particular set up.

Mac
 

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Ok, so I think both Cali and Rio are agreeing with me....

My point is that many of the AHJ's that I deal with only require 2 lateral hold downs and I don't believe that two of the DTT2's will provide sufficient lateral support for more than a very small deck. It's not really an issue for me as we have virtually zero seismic activity but I think an engineer could figure it out pretty quickly. A call to Simpson could probably get the answer in a hurry too as I'm sure they have done all this math before they started horning it into the code books.:rolleyes:
The detail I posted is basically identical to the one in the current Simpson catalog and is called out as a 'typical deck to house lateral load connection' and calcs out for the 'allowable tension load' to be 1,825 lbs in DF/SP and 1,440 lbs in SPF/HF. If I remember correctly the default required lateral resistance connection in the IBC/IRC for decks has the same requirement.

While Simpson undoubtedly takes advantage of the situation I don't think the people writing the code books need any encouragement to be overly zealous in their pursuit of an ever changing perfect structure. They've been drunk with their own power for far too long.
 

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The detail I posted is basically identical to the one in the current Simpson catalog and is called out as a 'typical deck to house lateral load connection' and calcs out for the 'allowable tension load' to be 1,825 lbs in DF/SP and 1,440 lbs in SPF/HF. If I remember correctly the default required lateral resistance connection in the IBC/IRC for decks has the same requirement.

While Simpson undoubtedly takes advantage of the situation I don't think the people writing the code books need any encouragement to be overly zealous in their pursuit of an ever changing perfect structure. They've been drunk with their own power for far too long.
There was no study that prompted those. They just thought it was a good idea.
Deck Lateral Loads, testing reveals answers: http://youtu.be/TsbZtNBteS8
 

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I was using 16d 3 1/4" nails in the holes of the holddown. The 2x4 scab was so the nails wouldn't punch through the side of the house as I was attaching holddown to the end joist. All nails go through hold down, 2x4 scab and 2x8 house joist.

And I've had engineers spec DTT2Zs in that particular set up.

Mac
Mac, I can say that is the best way I've seen yet on the installation of those things. Thanks for that! Definitely less destructive then opening up the home.
 
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