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how to build some slopes

Anonymous
Not applicable
Hello.
I have the following concrete construction to build and I do not know to choose between the slab, mesh and roof tools, in order to solve it.
For meshes, I noticed I can only elevate points, I cannot tell a pitch.
In my project, the slopes need to be 1.5% and what I need to find out are the differences in height between the defining points. Therefore, I do not think I can use the mesh.
For roofs, however, I see I cannot indicate a pitch lower than 1.75%.
How can I solve all this?
Thank you very much.
4 REPLIES 4
Barry Kelly
Moderator
Multi-plane roofs can not have a pitch less than 1.75% (1°).
However a single plane roof (which would be much easier to use here) can be flat or even have a negative slope.

So use the ridges as your pivot lines and set a -1.5% slope.
Then manipulate the shape just as you would a polygon or you can select one roof and CTRL click the edge of an adjoining roof to automatically trim that edge into the correct position (that's the way we had to do it before multi-plane roofs).

If you know the heights of your ridges then use that straight away when placing the roofs.
If not don't worry, just place the roof and figure out its shape, then elevate it to the height you want afterwards.

Barry.
One of the forum moderators.
Versions 6.5 to 27
Dell XPS- i7-6700 @ 3.4Ghz, 16GB ram, GeForce GTX 960 (2GB), Windows 10
Lenovo Thinkpad - i7-1270P 2.20 GHz, 32GB RAM, Nvidia T550, Windows 11
Anonymous
Not applicable
Thank you for your answer.
In other words, the solution lies in building single-plane roofs, one at a time. Am I right?
Thank you.
Barry Kelly
Moderator
igreere wrote:
Thank you for your answer.
In other words, the solution lies in building single-plane roofs, one at a time. Am I right?
Thank you.
That's right.

Barry.
One of the forum moderators.
Versions 6.5 to 27
Dell XPS- i7-6700 @ 3.4Ghz, 16GB ram, GeForce GTX 960 (2GB), Windows 10
Lenovo Thinkpad - i7-1270P 2.20 GHz, 32GB RAM, Nvidia T550, Windows 11
[Unless I am assuming horizontal lines where there are not, or ridges where there are walls, those will be different slopes (pitches), because you have slopes of different lengths getting to the same point. Also some of the maximum slope arrows appear to be impossible.]

In any case, the mesh tool is definitely the tool for laying that out: measure your longest slope and calculate the elevation of the most distant point for the minimum 1.5%, and all the rest will be fine. Also the mesh will triangulate everything and show you the ridges/channels you are missing.

If at any point you need to turn whatever you get into some slab with constant thickness, or a composite, there is/was somewhere a mesh-to-roof add-on goodie or whatever (main advantage would be that you could use skylights for openings, or some roof pitch marker—but in this structure I think everybody will care about point elevations and nobody about the precise slope to a fraction of a nothingness). And/or you can get a more buildable reasonable approximation to constant thickness by dragging the mesh whatever thickness you need down, using SEO to subtract the mesh below from the mesh above, and converting the result into a morph.
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