Lowering pitch of canted queen post barn roof

[Shandog]

I was wondering if anybody has every lowered the roofline on a canted queen post barn ? I am new to this site and hope I am asking this question in the right place 
Thanksc

[Don P]

Hi Shandog, I'm mostly bumping your post hoping someone with more experience will chime in. I imagine the same rule that applies to braced rafter framing and good truss design would come into play. That is, don't lay the posts over at shallower than a 45 degree angle.

As the pitch gets shallower the tension on the tie increases, which means the heeljoint needs to do more work as the pitch drops.

Do you have a sketch of what you are thinking of that you can post?

[Shandog]

Don 
 Right now the rafters are a 9/12 pitch call it 37 degrees and the canted queen post is at 53degrees making a right angle in the center of the rafter span with the brace being at 53 degrees also I want to lower the pitch to a 7/12  which is 30 degrees that would make the post more upright at 60 degrees and I would also make that brace at 60 degrees the purlin wouldn't be in the exact center of the rafter but the span is only 10' and about 12' above the purlin so spans with 2 x 10 should be fine   I am not sure how to upload photos at this time but will work on it 
Thanks 

[Jim_Rogers]

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[Don P]

That was the lawyer part, I guess Jim is saying to post your sketch not someone else's copywritten plans. This is a link to the tutorial on how to upload pics;
https://forestryforum.com/board/index.php?topic=100194.0

I guess basically with my understanding I'm looking at it not as a truss but as a tie beam, supporting posts, that are in turn supporting the rafters. But a sketch would sure help.

[Shandog]

 

 

[Don P]

[Don P]

Well, I got the pic posted but couldn't write anything there :D
You can click the modify button on your posts to try to fix things when they go wrong.

From a gut level the geometry looks ok to me. The right canted post and both struts are landing out in the span of the bottom chord putting concentrated loads from the roof on it plus whatever floor load is there, plus the dead load of the associated parts. Checking that is outside of my simple skill set.