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Roof Tool Negative Pitch - for Drainage Plan Floors




If it would be possible to use the roof tool with a negative pitch, modelling floor elements for drainage plans would be so easy. 




Thank you:)

Erwin Edel

Just split to single plane roofs and flip the pivot line.

Erwin Edel, Project Lead, Leloup Architecten

Windows 10 Pro
Adobe Design Premium CS5

It is possible. Just mirror each roof segment, so the pitch mark for each segment will be in the middle. You'd need to use the single plane geometry method for that.

For solid structures with a leveled bottom side the mesh tool is a better choice.

| Archicad 4.55 - 27
| HP Z840 | 2× E5-2643 v4 | 64 GB RAM | Quadro M5000 | Windows 10 Pro x64
| HP Z4 G4 | W-2245 | 64 GB RAM | RTX A4000 | Windows 11


I know it is possible, its just that with a minor change to the tool like this, a lot of time would be saved. Also if there ever is a change to the drainage-plan and some drains have to be relocated -- you would have to change every roof element and adjust them to the new plan. When were working on large projects, this can take quite a while to do.

May be you can develop such element in Param-O easily, so can get repeated or modified easily as when needed.




Construct required roof in shape of expected drainage element with its apex towards +ve Z axis. Convert the roof into Morph. Later rotate the morph to get the drainage element upside down.

Rajesh Patil
AC 09-27 | INT | WIN11 64
Dell Inspiron 7591, Core i9, 9880H 2.30GHz, 16.0GB, NVidia GeForce GTX1650, 4.0GB, SSD Internal 500GB, Dell SSD External 250GB

Using the mesh tool could also be an option for modelling drainage, in my opinion it depends on the situation which one is easier to use. | actively using: AC25-27 INT | Rhino6-8 | macOS @ apple silicon / win10 x64

Just use single-plane roofs, which you will need to in any case as soon the model gets past the very first rough sketch. Screen Shot 2021-09-24 at 1.01.29 PM.png

Vasileios S_

Can we just stick to the wish that Jensth made? He wants a roof with negative pitch, I want that too.

You cannot build a line.
jens thommesen

Anyone still interested in this? It would certainly make modelling detailed flat roofs very simple as well.

People have suggested multiple workarounds, which I appreciate, however the methods described are quite extensive and laborsome - which I hoped could be reduced by this change to the roof tool.




Your first sketch is what you get using the mesh tool. Just use the desired material and element classification. This one we already have.

Your second sketch is something you can get using the roof tool, but you need many clicks for getting it right.. I would prefer the mesh tool to have this functionality.

| Archicad 4.55 - 27
| HP Z840 | 2× E5-2643 v4 | 64 GB RAM | Quadro M5000 | Windows 10 Pro x64
| HP Z4 G4 | W-2245 | 64 GB RAM | RTX A4000 | Windows 11

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