Hi David - you're 100% correct. I agree with everything you've said and that's how I detail framing. This PDF was made before adding any detail lines or components. What I have shown is how the wall section looks as a result of joining the wall to the roof.
As I staed in my previsou post, the snapping issue is not isolated to just dimensions. If I try to draw a detail line or add a detail component - such a a 2x6 in section for the top plate - Revit will not recognize the intersection of bottom of rafer and top of stud wall. It will snap to the intersection of drywall on the sloped ceilign and drywall on the wall face.
No one cares what the dimensions of the drywall intersection is! The critical point is the top of wall, and when the wall and roof are joined, that's what Revit will not recognize. I have to add reference planes by offestting the RP fromt he floor level and outside face of framing.
So frustrating, not to mention time consuming for such a seemingly simple - and critical! - dimension task.
I guess thats what I'm getting at: you wouldn't ever dimension to that "point" shown in the PDF, but you are jumping through hoops to try and make it work. You would detail the connection, using the Cut Profile tool, to show the wall top as being level, and to show the rafter with the birdsmouth cut, and then dimension to the top of the top plate which is an easy dimesnion to show, and you wouldn't have to use any reference planes.
Furthermore, in your PDF, there is no Level Line defining the "Top of Wall" and there probably should be. Then you could dimension the "wall height" to that level line to properly call it out. You can also change the dimension to "faces of core" which will help snap it to the face of stud, instead of the "wall face" which in your case happens to be the outside edge of the drywall.
There are many ways to get the "proper" wall height dimension which do not require the number of work arounds that you are using such as reference planes.
That point in my PDF is the top of wall, even though it's not shown graphically correct. Same distance from floor level as you're describing.
Still being new to Revit, I haven't used the cut profile tool - thanks for that tip. When I use that tool, I now have the top of wall square as it should be, and I can dimension to that line. Great!
I can also add a detail component, such as a 2x6, and align it to reference planes, and that will hide the sloped line of the rafter in the wall cavity and give me a point to dimension to. Revit will even snap to that point of wall rafter-wall when I move the 2x6 component. Great!
However, I'm discovering that the cut profile tool is view specific. If I have three wall sections along the same wall, all with the same plate height and roof condition, but showing where other conditions are different, I have to use this tool in each view for each wall-roof connection - once for each wall and once for each roof. It does show the condition graphically correct - which is essential - but for dimensioning and detailing pruposes it's no less work that adding reference planes.
It seems silly to have to join a wall and roof to get them to show correctly, yet not quite, and then to have to use another tool to clean up what should be shown correctly by the software in the first place.
Why isn't there a wall-roof join tool similar to the wall join tool where different wall joins can be scolled through to selet the appropriate one? Or, why isn't there a wall join option built into the roof tools that allows for a bird's mouth cut vs. no cut on the rafter? When framing with 2x lumber we use a bird's mouth cut, but when framing w/ TJI's we don't cut the bottom cord, instead it's aligned to the outside face of stud & top plate and attached with a connector. The most standard, common practice in wood frame construction. This would seem to be a simple option to add to the roof tool, since there are already similar options such as truss vs rafter.
After all of this, I think it's easiest to add (2) 2x6 detail components as it hides the sloped rafter line in the cavity and gives a point to dimension to.
RE: dimensions - mine are already set to "face of core" - not to "wall face" as you are assuming - and still I cannot select the point in question.
RE: levels for top of wall/plate - I'm on the fence about adding those. The majority of my work in on very steep slopes; this house already has 7 levels for floors and a couple of other misc levels. There are many wall plate heights. If I add one for each wall height, then I've got more levels to manage as I don't want each wall height level to show in each view. A lot of levels to manage in all the elevation & section views.
I've been looking at levels as being specific to floors, but I see an argument can be made for adding levels to wall plates. It would make changing a wall height easy by changing the elevation of the level. To do that my roofs would have to have a 0'-0" offset from that wall height level.Just thinking out loud... not sure if this would be a good practice... If I keep the roofs associated to the floor level, then what's the point of having a level for wall height?
Thanks for your help David. mpp