Roof Structure & Material Layers

[JLU_Design]

I'm having an issue with how the roof layers populate in Chief Architect.

I want the roof "surface layers" to all be above the "fascia top height".

Right now it always starts the roof "Surface Layers" 7/16" below the "Roof Plane Line".

When building we align the outside corner of the face-board with the top plane of the "roof structure", Trusses or Rafters which should be the roof plane line.

The OSB, Underlayment, and Shingles rest on top & outside of the face-board / "fascia top height" that is aligned with the top of the roof structure.

Chief Architect consistently lowers the roof structure 7/16" (in plane with the roof surface) from the "Fascia Top Height" no mater the pitch.

In order to get things to work I have to add a 7/16" layer to the "Roof Surface" and Subtract 7/16" from the "Roof Structure" (e.g. rafters) in order for the cross section to show the layers correctly.

This works for any pitch meaning that the roof is dropped 7/16" (in plane) with the roof surface.

The reason this is important is because I need to show Fascia Top Height in Elevation Dimensions and if I have to shrink the framing members, they are not modeled / sized correctly.

I'd like to know if there's any way to adjust this default "Fulcrum" without the hackey way I'm doing it.

I want to be able to specify the fascia top height and have roof planes properly populate from that point.

 

It's important to note that in this image both "Fascia Top Heights" are the same with the only difference between the two being the one on the left is a 7/12 and the one on the right is a 4/12.

Where the green lines intersect represents the "Fulcrum" that the roof revolves around at the outside of the face-board by default and the red line shows the default top of the "Roof Structure".

I have to add a 7/16" layer between these planes in-order to get the OSB to be above the green roof plane line & top of face-board.

The roof "Structure" is always 7/16" in plane below the "Fascia Top Height" / "where the green lines intersect" by default from what I've been able to figure out.

I'd like to know if I am missing some setting that could change the "Fulcrum" point in relation to the roof layers.

I've spent allot of time figuring this out but have not found a setting to fix this yet.

[Chopsaw]

I don't seem to be having that issue.  You may need to tell us what version you are using and post a test plan.

 

[glennw]

Are you after something like this?

Do you only want the subfascia and not the eave fascia?

[JLU_Design]

9 hours ago, glennw said:

Are you after something like this?

Do you only want the subfascia and not the eave fascia?

This is exactly how I want the components to be organized.

 

When I specify Fascia Top Height-

It should be at this point.

Top outside corner of Eave Sub Fascia shown above.

 

With all the Roof Layers/Surface above the line shown below:

And all the Roof Layers/Structure below the line shown above.

 

The way to check is to select the roof plane and specify the Fascia top height you want and then do a cross section and pull a measurement from 0" to the top outside corner of the fascia you should find that the Fascia Top Height does not correlate with the plane line between the Roof Structure Layers and the Roof Surface Layers.

 

I'll illustrate this below:

 

Select the roof plane and specify the composition:

Specify the Fascia Top Height:

In the Cross Section draw a cross box (Representing the Fascia Board) at the specified Fascia Top Height.

Use a measurement to confirm the height:

Closer View of the same roof plane Cross Section showing how the OSB is below the Specified Fascia Top Height:

Same roof plane Cross Section illustrating a rafter with attached finished ceiling:

If I have a specific Rafter/Structure Depth with the Ceiling attached to the bottom of the Rafter, In this case it's too low because the OSB is not above the Fascia Top Height.

 

 

Thanks, Your detail was perfect to illustrate.

 

Edited September 15, 2021 by JLU_Design
Added a few notes to clarify the details.

[Chopsaw]

38 minutes ago, JLU_Design said:

If I have a specific Rafter/Structure Depth with the Ceiling attached to the bottom of the Rafter, In this case it's too low because the OSB is not above the Fascia Top Height.

 

So the issue is that the Fascia Top Height is incorrectly reported in the Roof Plane Specification DBX ?

 

That is not exactly true.  What you are illustrating is the Sub Fascia which is not reported at all in the Roof Plane measurements.

 

The Fascia actually builds to the displayed Fascia Top height.   So  possibly for your situation you should make a feature request that the Sub Fascia height should be displayed in the Roof Plane DBX.   Would that help ?

[JLU_Design]

Here is another illustration.

[robdyck]

2 minutes ago, JLU_Design said:

Here is another illustration.

Several versions ago, Chief did indeed use the logical fascia height, that is the top elevation of the sub-fascia. There also was a time when one could group select roof planes and make an adjustment using the fascia height, which currently remains greyed out for this type of function.

This issue has been raised and suggested repeatedly, but for some reason we are stuck with one data point that indicates a finish material as opposed to the actual structure.

 

Currently there is no way to alter this. Rather one must specify elevations based on the Baseline Height or Ridge Top Height. Keep in mind that for a Baseline Height to be utilized correctly, you must be aware of where it located in plan view.

 

Side note: finished fascia and shadow boards should build OUTSIDE of the roof plane line, or at least we should have that option.

 

[JLU_Design]

10 minutes ago, Chopsaw said:

 

So the issue is that the Fascia Top Height is incorrectly reported in the Roof Plane Specification DBX ?

 

That is not exactly true.  What you are illustrating is the Sub Fascia which is not reported at all in the Roof Plane measurements.

 

The Fascia actually builds to the displayed Fascia Top height.   So  possibly for your situation you should make a feature request that the Sub Fascia height should be displayed in the Roof Plane DBX.   Would that help ?

 

I was hoping someone would know of a setting to change this.

 

The way it is the roof Fascia Height is more or less just an arbitrary number.

In real life the most accurate way to specify roof height is to specify the overhang length and the top of Fascia Height in relation to the top of the wall or from 0" in elevation view.

 

All we need is the line between the roof structure and roof material layers to intersect with the "Fascia Top Height" and all of this would be resolved.

Then if someone wants the roof sheeting below that line they can just add it to the roof structure layers.

Or if like me I want it above the fascia top height I'd just put the roof sheeting in the roof materials layer.

 

I really like the new dialog in X13 for the Wall Type Definitions, I wish they could do something like that for the roof plane composition.

It seems like it would be way more versatile.

Notice on this dialog I wanted the wall sheeting to be part of the main layer because of how we build in our area. This was very easy to accomplish with this dialog:

 

I'm new to this, how does one make a feature request?

 

Thank you all for your input.

[Chopsaw]

3 minutes ago, JLU_Design said:

I'm new to this, how does one make a feature request?

 

Feature requests can be made in the Suggestions forum.  https://chieftalk.chiefarchitect.com/forum/8-suggestions/

 

Are you clear now on the distinction between the "Fascia" and "Sub Fascia" ?  It is done all different ways in different areas but the Sub Fascia is generally structural and the Fascia is mostly decorative.

[JLU_Design]

4 minutes ago, Chopsaw said:

 

Feature requests can be made in the Suggestions forum.  https://chieftalk.chiefarchitect.com/forum/8-suggestions/

 

Are you clear now on the distinction between the "Fascia" and "Sub Fascia" ?  It is done all different ways in different areas but the Sub Fascia is generally structural and the Fascia is mostly decorative.

Thanks

 

Yes, I know the difference between finish fascia and sub/structural fascia.

Horizontally I would prefer if the start point of the angle for the roof plane would be between the finish fascia and the sub fascia.

Right now it's on the outside of the finished fascia from what I can tell.

Finished fascia is generally treated like cladding on a building in our area. For example all dimensioning is done to the sub fascia and the outside of the main wall framing layer.

Vertically the start point of the angle for the roof plane should be between the roof structure layers and roof material layers using chief's naming scheme.

If a dialog was used like the wall type definition dialog those dimensioning preferences could be accounted for like they are in the wall settings.

 

Thanks for your consideration, I appreciate it.

 

[Chopsaw]

Yes it is quite helpful to get opinions from experienced builders from around the country, so please post in the suggestions forum and the discussion can continue there.  What we have now is a result of what I suggested a while back to match the roof framing setup to the wall framing setup just as you have suggested but they did not go quite as far as I think would be helpful.