Replying to Bonus Room Roof

Well if you have the joists bearing on that wall than the plate will have to sit on the floor. Referencing the wall below would cause the floor joist to stick out. 

If the joists are not bearing on that wall then there is no need to have a plate there on the second floor.

It is a very rare case where you would need to reference a first floor wall which is directly under a second floor wall. 

While it is not uncommon to see solid lumber cut to match the outside of the rafters it is not good practice. 

But if that is the intention than there is no need to have a wall there on the second floor.

I'm not sure why you would want to have the plate if the rafters were to sit on the 1st floor wall, other than showing to show the outline of the wall below. I think the best solution for what you are trying to do is to edit the plate definition, and save as another plate called something like "Non-Bearing Plate", and uncheck bearing. Non-bearing walls are not visible in roof mode.

There must be a good reason why softplan doesn't have an option to reference the roof edge from the second floor to the first but I don't know what it could be. It seems so simple to have.

I have used the method of adjusting the 2nd (or 3rd) floor wall to gain access to the lower floor wall.  But, I have found that once you get it looking the way you want, turn off the cleanup option for that roof section.  Actually I find myself doing this for every multi-floor roof (turning off cleanup when it is correct).

Yes that is true. You have to temporarily adjust the second floor wall so that you can reference the first floor walls.

Not the best solution for this case but is sometimes useful for complex roofs where you need to establish a roof plane that is mostly covered by the second floor.

Also it is sometimes necessary to draw walls which are hidden and only used to reference the roof. 

I do not know what the benefit of not showing the plate on the second floor plan would be since the actual house will need one. And this produces an accurate plan and material list. 

That's where I suggested putting the plate on a different layer so you could hide it when you input the roof (essentially the same concept as cutting the wall). You could also set the plate offset on the 2nd floor to the same height as the top plate of the 1st floor wall. Another option is not using a wall/plate at that location on the 2nd floor, you can just use dashed lines to depict the plate on the 2nd floor plan. Just suggesting some other work-arounds.

I must be missing something. While in multiple floor roof if I have a 2nd story wall directly over the first floor wall the roof edge always goes to the 2nd floor wall. The only way I have found to get it to reference the first floor is to cut the 2nd wall just enough to let the roof edge reference the first floor.

You do realize that you can reference the lower floors walls by choosing "Multiple Floor Roof" while in Roof mode.

Phil

Thanks Guys. Keith that was exactly what I was looking for. Using the plates worked great. I still wonder why there can't be an option in the roof edge to reference the lower floor walls.

It sounds like want to show walls at the outside perimeter of the bonus room on the 2nd floor or attic plan. If it is being conventionally framed, I add a floor system the same the same as any 2nd floor, then use a plate above the floor sheathing to reference the roof. If fascias have to align and that raises the heel too much for your application, you can put the plate on a different layer and turn off the visibility, then reference the 1st floor wall when you input the roof.

If it is a trussed roof, the component manufacturer can accommodate pretty much any heel height (4 5/8" is usually the minimum). If the attic room has a 2x10 for the floor, the bottom chords can always be reduced outside of the attic room to 2x6 - this may reduce the cost of the truss as well. In cold climate zones, insulation value usually governs the heel height required.