Simpson DTT1Z and DTT2Z Deck Tension Ties

[Northriver]

Decks in WA State as well as CA have had load ratings of 60# dead and 10# live loads for the last 3 years and since 2015 have had to add deck tension straps. In the new updated 2015 Simpson catalogue they have added the DTT1Z and the DTT2Z. I made some details showing each as I am trying to get away from PDF's.

They are drawn at scale (1to1)and the text size is 2". They have been blocked so if you want to make modifications just un-block and adjust line weights, change text ect......

I have taken from this forum so I thought I would give back.

DETAILS.plan

[AndyGump]

Well thank you sir.

 

Andy.

[Greg_NY61]

Thanks for sharing... But you have to make some adjustment to your detail, DTT1Z Deck tie must be attached to the sill plate not the rim joist.

[Northriver]

Thanks for sharing... But you have to make some adjustment to your detail, DTT1Z Deck tie must be attached to the sill plate not the rim joist.

 

I called simpson and got clarification on that on last Wed. I told them the diagram shows lag screw mounted in the plate but what do you do if the is deck joist is smaller than the interior joist. I was told It has to have 3" of penetration weather in the sill, header, stud or joist (2x8 min). It can also be thru bolted as well.The reason for the DTT1Z was for easier installation. I should have mentioned though that the holes are to be pre-drilled for lag bolts but that should be common sense.

 

I noticed the code book has no lag bolt placement requirements for in the rim joist for 60# live load decks only for 45# live load. My engineer has been requiring 2- 1/2" x 4" lag bolts staggered in every joist bay for spans up to 14' and 3 staggered after that.

 

You are correct though as that is the way it is drawn in the catalogue. But if you read the text it says it can attach to plate, header, stud or joist. Could you possible have an older catalogue?

 

PS: We no longer can use 2x6 PT for decks anymore.

[Greg_NY61]

I called simpson and got clarification on that on last Wed. I told them the diagram shows lag screw mounted in the plate but what do you do if the is deck joist is smaller than the interior joist. I was told It has to have 3" of penetration weather in the sill, header, stud or joist (2x8 min). It can also be thru bolted as well.The reason for the DTT1Z was for easier installation. I should have mentioned though that the holes are to be pre-drilled for lag bolts but that should be common sense.

 

I noticed the code book has no lag bolt placement requirements for in the rim joist for 60# live load decks only for 45# live load. My engineer has been requiring 2- 1/2" x 4" lag bolts staggered in every joist bay for spans up to 14' and 3 staggered after that.

 

You are correct though as that is the way it is drawn in the catalogue. But if you read the text it says it can attach to plate, header, stud or joist. Could you possible have an older catalogue?

 

PS: We no longer can use 2x6 PT for decks anymore.

We use now ADTT-TZ Tension ties much easier to use and easy to adjust in any situation.

 

They come in flush or full extension and they exceed 2015 IRC lateral attachment requirements, just have to check with your building department if they heard about them yet, because some of the building officials have no clue, so you have to provide them with literature.

[Northriver]

Greg, how are those attached to the interior of the building? They look really easy to install. The framers like easy.

 

Thanks for the input.

 

PS: Your alias is badass. I like it.

[Greg_NY61]

Greg, how are those attached to the interior of the building? They look really easy to install. The framers like easy.

 

Thanks for the input.

 

PS: Your alias is badass. I like it.

You don't attach them to the interior, you screw them in into the plate from the outside same as you do with DTT1Z. They adjustable and can be moved up and down, in and out.

[chief58]

Jeff thank you very much for sharing and your time putting into this much appreciated

[Northriver]

My pleasure Ray. I just wanted to try and give something back to the Chief community as I take way more than I give.

I am currently re-drawing my details that are in PDF format to help reduce plan file size. As I go thru them and find some that may be of interest to others I will post them. I actually enjoy drawing details using the cad tools. Chief could do better by improving these tools more inline with Vector works and ACAD but it seems to be not that important to most users.

Thanks

[Joe_Carrick]

Thanks for sharing... But you have to make some adjustment to your detail, DTT1Z Deck tie must be attached to the sill plate not the rim joist.

Greg,

 

Obviously you mean the "Top Plate".  It would be impossible to attach to the "Sill Plate".

[Northriver]

Thanks for the clarification Greg.

I found out that these are made by USP. I showed one of the framers onsite and they liked the USP version as they look easier to install especially on a deck low to the ground. Unfortunately in WA State USP products are not readily available as Simpson dominates the market here as they have a distribution center in WA that can also custom make hardware and get to the field in a timely matter.

[Northriver]

Joe, it can be attached to any plate, stud, header or joist. I think it could be attached to the sill plate depending on how the deck was built?

[Joe_Carrick]

Normally the Sill Plate is above floor sheathing which is of course way above the bottom of the Deck Joist so I can't see how that would be possible.

[Northriver]

Joe you are absolutely right but I think he meant mudsill. I meant mud sill too on my last post. Sorry should have clarified. One word can make a difference in an explanation of doing something right or doing something wrong.

I am glad you are keeping us honest.