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I am building rafters to connect to a ridge board for a shed and I am torn between the rafter hangers to use. These are the two options:

enter image description here

The reason I am torn is that the one RR rafter hanger is cheaper but looking at the design the rafter will never be flush to the ridge board and the connector only goes down about halfway on the plumb cut so really there will be a slight gap (this is also the rafter hanger I’ve seen in a well done YouTube video on building rafters). Is this going to be a problem? The LRUZ hanger though does allow the plumb cut of the rafter to be flush against the ridge board but is double the cost. Also from a physics standpoint, I would assume that’s important for there to not be a gap but why would Simpson make a product like that then?

https://www.lowes.com/pd/Simpson-Strong-Tie-LRUZ-ZMAX-174-Galvanized-Slopeable-Light-Rafter-U-Hanger-for-2x6/1002623542

https://www.lowes.com/pd/Simpson-Strong-Tie-RR-Ridge-Rafter-Connector/1203733

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As you can see in Simpson’s structural notes, the LRU is rated: Uplift = 660, Floor load = 935, Snow load = 1075 and Roof loads = 1170 lbs. as seen here:

https://www.google.com/search?q=simpson+tie+lru26z&rlz=1CDGOYI_enUS900US900&oq=simpson+lru26z&aqs=chrome.1.69i57j0i22i30.22602j0j7&hl=en-US&sourceid=chrome-mobile&ie=UTF-8#imgrc=MXNRLopEfhaVDM

But the Simpson RR Ridge Rafter Clip is only rated for Uplift =130 , Floor load =330, and Roof load = 330 lbs., as seen here:

https://www.strongtie.com/topflangehangersssl_solidsawnlumberconnectors/rr_connect/p/rr

So the hanger is clearly stronger than the clip.

There’s good, better and best in everything. Do you need the best?? If so it will cost you… like most things.

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  • What is your thoughts on the RR connector not allowing the plumb cut to be flush with the ridge board? Also do either connectors reduce the need for collar ties? Nov 21 '21 at 23:02
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    I don’t understand your statement that “the RR connector not allowing the plumb cut to be flush with the ridge board”. I think the joists could be cut plumb for either connector and have the end of the joist fit tight against the face of the ridge board (AND the top edge of the joist to align with the top edge of the ridge board if desired.)
    – Lee Sam
    Nov 21 '21 at 23:51
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    Collar ties at/near the ridge are not required for either connector if the ridge board is supported at both ends. The ridge board then becomes a ridge “beam”. Then the forces from the joists are acting directly vertically… there is no outward thrust. However, if the ridge board is not supported at both ends, then neither connector can eliminate collar ties.
    – Lee Sam
    Nov 22 '21 at 2:14
  • There is some dimension to the RR connector so as shown in the picture it does not sllow the rafter to sit flush wood to wood against the ridge board. That is where I was concerned. I was under the impression collar ties could be eliminated for a ridge board using certain metal connectors. Maybe those are ridge straps such as Simpson HRS12. Nov 22 '21 at 2:28
  • Btw, the structural strength of the joists are calculated based on the horizontal distance between supports, not the length of the board. So, the horizontal distance between supports might be 12’ but the overall length of the joists might be 14’ long. So the structural calculations are based on 12’ not 14’
    – Lee Sam
    Nov 22 '21 at 5:18
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Both hangers are designed for connecting the inclined rafter/joist to the ridge board or ridge beam, the difference is the structural strength. Rather than making your own choice, you shall get direction from the roof designer as to which is best fitting your need, or at least consult with an experienced contractor.

Below are the finished views of connection use each type of hanger. Note that RR hanger is often recommended for lean-to roofs.

enter image description here

enter image description here

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