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Modeling
About Archicad's design tools, element connections, modeling concepts, etc.
SOLVED!

How to Connect Angled Roof to Horizontal Slab for a Clean Top Connection?

Heftor
Booster

Hello,

I'm working on a building design that features a roof connection I'm struggling to model correctly. I've spent some time trying different methods without success and was hoping for some guidance.

 

My Goal:
I need to connect a pitched, angled roof to a horizontal slab so that the top surface of the slab is horizontal and aligns flush with the angled roof. Essentially, the slab should act as a parapet or a flat surface that the roof butts up against from the side.

Heftor_0-1756126901691.png

Heftor_1-1756126967110.png

 

But, No matter which combination of methods I use, I can't get a clean connection. The roof either doesn't trim the slab correctly, leaves a gap, or the slab cuts into the roof's structure instead of just meeting its top surface.

 

Heftor_2-1756126984523.png

 

Heftor_3-1756126999399.png

 

 

I've used the Connect tool with nearly all variations:

  • Targets: I've tried selecting the Slab as the target and the Roof as the operator, and vice-versa.

  • Geometry Methods: I've experimented with Subtract, Subtract with Upward Extrusion, and Subtract with downward Extrusion.

The results are always messy. The most common outcome is that the slab gets cut on an angle following the roof's pitch, which is the opposite of what I need. I want the roof to be trimmed to meet the horizontal plane of the slab.

 

Am I using the right approach with the Connect tool, or is there a completely different method I should be using for this specific detail?

Does anyone have a proven workflow or any tips for creating this kind of roof-to-slab connection cleanly?

 

Any advice would be appreciated! Thank you in advance for your help,

Hector

 

Operating system used: Windows

1 ACCEPTED SOLUTION

Accepted Solutions
Solution
runxel
Hero

Don't use a slab but a 0° roof. Then just use the ctrl+click method to join them automatically.

Lucas Becker | AC 27 on Mac | Graphisoft Insider Panelist | Akroter.io – high-end GDL objects | Author of Runxel's Archicad Wiki | Editor at SelfGDL | Developer of the GDL plugin for Sublime Text

My List of AC shortcomings & bugs | I Will Piledrive You If You Mention AI Again |

POSIWID – The Purpose Of a System Is What It Does /// «Furthermore, I consider that Carth... yearly releases must be destroyed»

View solution in original post

3 REPLIES 3
cuba
Expert

Easiest connection is by drawing the slab as a roofplane en connect the two roofs.

Apple M1 Max 32 GB Ventura
AC27
Solution
runxel
Hero

Don't use a slab but a 0° roof. Then just use the ctrl+click method to join them automatically.

Lucas Becker | AC 27 on Mac | Graphisoft Insider Panelist | Akroter.io – high-end GDL objects | Author of Runxel's Archicad Wiki | Editor at SelfGDL | Developer of the GDL plugin for Sublime Text

My List of AC shortcomings & bugs | I Will Piledrive You If You Mention AI Again |

POSIWID – The Purpose Of a System Is What It Does /// «Furthermore, I consider that Carth... yearly releases must be destroyed»
Heftor
Booster

Hi @runxel and @cuba 

 

Thanks for the tip, it looks nice now

Heftor_0-1756132948886.png

 

Regards,

Hector

Setup info provided by author