Question about roof and baselines

[Jambruins]

If I want the top of all of my walls (house and garage) to be at the same height and then have all of my trusses start at this point do I control that by locking the baseline height at the same elevation for all of my roof planes or is this done some other way?

[robdyck]

28 minutes ago, Jambruins said:

If I want the top of all of my walls (house and garage) to be at the same height and then have all of my trusses start at this point do I control that by locking the baseline height at the same elevation for all of my roof planes or is this done some other way?

Yes...ish, but keep in mind that the location of the baseline in plan view matters as well. You really shouldn't need to think about the baseline. Rather, all your rooms should have the same ceiling height. Then, you'll want to make sure your roof height factors in 2 things for trusses:

1. Raise / lower from ceiling height (for my region that is typically 3.5") or think of this as the bottom chord depth
2. Roof Layers / Structure (for my region that is typically 3.5") or think of this as the top chord depth

These 2 items will help you define the heel height of the truss - which matches Chief's Baseline height. This is the vertical height to the underside of the roof sheathing at the exterior of the framing layer. Then, any roof plane you draw will have the correct 'Baseline" relative to the top of the wall that the roof plane was drawn over.

Quick example: In my region, the typical truss has the top chord 'pivoting' on the outer edge of the bottom chord.

 

[Jambruins]

thank you

[MylesRother]

I like the idea that in a simple design the baselines are all the same, but there are times when that just isn't the case.  In the drawing here the left side of that right gable has a baseline that is 2' higher than the right.  What is the best way to hand this in CA, and not have to move to manually drawn roof planes?

[Alaskan_Son]

1 hour ago, MylesRother said:

What is the best way to hand this in CA, and not have to move to manually drawn roof planes?

 

In my opinion?  There isn't one.  You can use all sorts of tricks to coerce Chief into modeling any number of non-standard roofs automatically, but I feel like it's easy to invest more time and expertise in doing so than it would have taken to simply model it manually.  My suggestion to you is to learn and master the manual roof modeling tools.  I think you'll find that once you've learned the tools, you'll have no qualms about simply turning auto off and manually modeling just about any roof you can think of.  From the looks of it, that scenario would take about 30 seconds to accomplish by simply turning auto off and manually adjusting.  Heck, I bet the whole roof would only take 5 minutes.