Thanx...... yeah that is the one and others similar I found the most informative. As that shows...... 1/3 the way up from typical joist location (x in the drawing) is what I mentioned earlier where one would put the new joist (collar tie).
Good thing is that Sandwiching AKA doubling collar ties allowing for every third. I had forgotten about that.
I wonder if it would allow for going every 4th or 5th rafter if you did an even stronger collar tie say double like shown as well as boxing in with another board on top and bottom. Followed by a triangulation to top of wall a little to each side; to spread this stronger collar's affects on the outer wall, This would be to my advantage cause it would look way less busy up there in that small space with less collar ties. I think my joinst are 18" on center........ a bit over kill. Also I want to loft a tiny sleeping loft in a portion of that cathedral space so those joist will be strengthened turning them into floor beams as well. Loft would basically center on the the *outer wall of original structure resulting in loft sitting with 1/2 of it above the addition and 1/2 above the original structure. It would be about 8" deep (red in picture)........ so yeah tiny. Could add header into walls of orginal structure to make them more "structural" and less divider walls to increase ability to hold up loft.
* in this case outer wall of original structure refered to here is now also an inner wall inside of addition
I've already looked and it appears I have a ridge board but not a ridge BEAM nor POST inside the wall too the foundation. (pier and beam foundation)
Moderator.......... feel free to dissect out the discussion in this thread on cathedral/vaulted ceiling and start a new thread with it.