So, if I got it right, Last stair elevation should be 2.70 minus the height of one stair.
No, in this case the display at the bottom "Last stair elevation" means the top of the last step or riser.With concrete: For a U shape you create a small (9 steps?) staircase, group the objects and copy the group. Create a single box for the landing. Elevate the landing and one of the staircases to the correct height. Of course first rotate one staircase to get the U shape in combination with the landing.
Just like furniture libraries you can import texture libraries. The AmbientCG library listed on this page is large and very good and has several different concrete textures.
I think there is a handrail in the furniture catalog but otherwise you can create them using cylinders.
--Please, tell me how you "custom create" your staircases, if it is not a trade secret.
It's no trade secret, just a lot of learning and getting experience. Lots of users here create their own furniture instead of downloading ready made models. I am such a nutcase that I create ALL my furniture myself, including doors, windows, and of course staircases.How? That's a long answer. Some time ago I started to create a manual for creating furniture but it soon was clear that it would become more of a book than a simple manual. I gave up on that, it became too much like real work
Basically you use objects like box, cylinder, and triangle and even walls and rooms. Or you can create custom shapes with the Generate 3D Shape tool. Resize, combine, and export to create furniture. There's much more to it of course but it is a little like drawing line by line only you use parts to create furniture. In some cases you need to use Blender because there are a few things you can't do in Sweet Home 3D. Blender can import and export the obj/mtl format so that's easy. It's also easy to edit the obj/mtl files to change material names but you have to learn how. My basic process is to create parts, export, edit material names, import. Next part. Then combine all parts and export/import as the finished furniture.
In this thread I offered a library with custom created public staircases: https://www.sweethome3d.com/support/forum/viewthread_thread,11998 . Not my the best work and it took way too much time. Nowadays I can do better and much faster. Maybe I'll update the library one day but it will give you an idea of what is possible. There are many more examples on the Sweet Home 3D site. On the sourceforge Sweet Home 3D many more examples are offered.
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