1.5 Story Gambrel Roof Modeling Issues

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I am attempting to model a structure with a gambrel roof that should rest on top of a 2 x 12 rim joist that sits on top of the first floor walls. Instead, the roof rafters keep resting on the top plate of the first floor walls, no rim joist generates on the hip walls. A screenshot from HD Pro 2021 and a sketch of the framing from AutoCAD is attached.


This is an existing house I am trying to as-built for a remodel. The first level is slab on grade with 2x12 ceiling joists that form the floor for the "half" story above. The steep pitch roof rafters should sit on top of this 2x12 floor system rim joist at the top of the hip walls. Where the roof changes pitch, the rafters are supported by a wall that rests on top of the 2x12 floor system. So no ridge rafters should be there. In the 3D model screenshot, the rafter support wall is in the correct location but the roof system is not generating correctly because it is resting on the top plate for the wall below instead of ~12" higher on the rim joist.


Thank you in advance for any help and let me know if I missed some needed details.



Home Designer Pro 2021



autocad gambrel framing.JPG

gambrel framing issues.JPG

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*** I see you said Pro 2021 ***



Answers often depend on which title (Suite, Pro etc) and version (2018, 2019 etc) you are using.


You can help everyone by adding that info to your signature (see below for how to turn them on) by clicking on your user name at the top right of the page, click Account Settings, then Signature on the left.


Doing so makes it always available, and keeps others from having to hunt for it.


And, turn on signature display too.






Resources for self help:


The built in Help System (always a good place to start)




Home Designer - Getting Started - Setting Preferences and Defaults
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Eric, thank you for the quick reply last night. I gave this a shot and the results in the screenshot below speak to my skill level :D I will play with this some more and see if I can get it to work. I thought the manual roof would overwrite the auto generated one. I drew it on the first floor plan and told it to ignore the 2nd floor. Not sure why it displayed the way it did.



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Eric, I don't know that I would have figured out the trick you found to generating the second story and then generating the roof from the 1st floor. Very helpful, thank you! I was approaching it from making the second floor zero height.


I was able to get this working on a brand new model I did from scratch, disappointing that I may have to rebuild everything from ground zero here. The original model in the screenshots I posted I started in Suite before I upgraded to Pro to address the inability to create this structure correctly. The Suite model keeps generating the original auto generated roof under the manually drawn roof planes. I am not sure how to shut off the auto roof despite unchecking auto rebuild. Even in the new model it did that a few times but I could see the roof planes in plan to be able to delete them, where I couldn't see the auto roof planes in the model started in Suite.


I love the 3D rendering in this software. However, I am noticing a lot of quirks (inconsistent behaviors) in the auto generated features and a lack of control, even in pro to disable some of these things. Its like the auto features are always fighting with the manual changes and if you don't create the model in a specific order it breaks. In other words, it doesn't seem that work flows are consistent forward and backward.


I'm in my 30 day return period on this and trying to decide whether to keep the software. As much as I want it to work, the frustration with fighting the sometimes helpful, sometimes detrimental auto features vs manual features is making me question if this will be a productive tool.


Initially, with no Home Designer experience, I was able to quickly create a model that resembled the existing home. As I go in to tweak the details to match and update the existing build I am finding it is taking many multiples of the initial modeling time trying to find which quirk will create the result that matches real life. Where accurate structural details and not just looks are important for creating useable plans I am concerned about this. I am certainly new to this software but have years of experience in AutoCAD 2D drafting, ProE and Inventor 3D parametric modeling so dealing with complex software isn't exactly new to me.


Are quirks a part of the Home Designer life or am I largely the cause?


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41 minutes ago, wranch said:

Are quirks a part of the Home Designer life


Yes they are. The key is learning and understanding the software, which takes study and practice.


With Pro, you do have manual tools that will often fill in when the auto tools are not working.

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