topic Re: Modeling an overlapping stair. Is it possible? in Modeling

Modeling an overlapping stair. Is it possible?

carloshcp — Thu, 25 May 2023 14:37:21 GMT

Hello!

I'm trying to model a stair that overlaps itself while it goes from one floor to another.
Archicad doesn't let me continue drawing the stair when it reaches the part from below.

I'm attaching an image to help understand my problem.
Is it possible to model only one stair or will I have to use 2 of them?

Tks,
Carlos

Re: Modeling an overlapping stair. Is it possible?

Eduardo Rolon — Thu, 24 Sep 2020 21:28:34 GMT

You'll need 2.

Re: Modeling an overlapping stair. Is it possible?

Laszlo Nagy — Sun, 27 Sep 2020 23:05:46 GMT

Yes, you will need to model it using 2 Stair elements, this is a limitation of the Stair tool in Archicad.

Re: Modeling an overlapping stair. Is it possible?

Eduardo Rolon — Mon, 28 Sep 2020 00:34:10 GMT

Not necessarily a limitation. Just the way it works.

Re: Modeling an overlapping stair. Is it possible?

Laszlo Nagy — Mon, 28 Sep 2020 00:57:51 GMT

Yes, true. It is just something some people may consider a limitation (myself not included).

Re: Modeling an overlapping stair. Is it possible?

Hmooslechner — Fri, 02 Oct 2020 14:03:40 GMT

Not overlapping? Of course, its a limitation. No user can find any useful point on that. Its just a decision of the programmers to make their lives easier, but i never heard of any benefits for the user. What shall that be good for - just to make it harder on special designs for the user.. And by the way - Rails can overlap with no problems. Nearly no problems except displaying it in different stories. But that would also be solveable.

Re: Modeling an overlapping stair. Is it possible?

Anonymous — Fri, 02 Oct 2020 14:37:56 GMT

I would say that it is a limitation that results in most cases in incorrect model when someone makes such stair in 2 pieces.
In most cases, the Riser Height is an uneven number and when you have to make 2 such stair that match, they never really do.

Say you have a height of 5000 mm and you need a spiral staircase. In many countries, it is permitted to have such "long" evacuation spiral staircase, but in the newer versions of Archicad, it is impossible to create it in one piece.

How do you do it then? Say you have 29 risers and a riser height of 172,413793... mm. There is no way to divide such stair and match it perfectly. So yes, I would definitely say that it is a limitation.

Re: Modeling an overlapping stair. Is it possible?

PVBergkrantz — Tue, 06 Oct 2020 07:54:06 GMT

mbl wrote:
How do you do it then? Say you have 29 risers and a riser height of 172,413793... mm. There is no way to divide such stair and match it perfectly. So yes, I would definitely say that it is a limitation.

What kind of stair producer do you use with that accuracy, I'd love a business card.

Re: Modeling an overlapping stair. Is it possible?

Anonymous — Tue, 06 Oct 2020 09:12:22 GMT

PVBergkrantz wrote:

mbl wrote:
How do you do it then? Say you have 29 risers and a riser height of 172,413793... mm. There is no way to divide such stair and match it perfectly. So yes, I would definitely say that it is a limitation.
What kind of stair producer do you use with that accuracy, I'd love a business card.

I don't care what is the "exact" Riser Height, I only care about the total height of the stair and I want that number to be even. And that's something that you can't achieve if you divide your stair like it is necessary for stairs with overlapping Baseline.

It's about correct model display in 2D and 3D, not about accuracy. Try stacking two stairs with such uneven height on the top of each other and then make the total height match with your top floor.

Yes, some people don't mind it there is a small height difference in the section for example, but I try to avoid such unnecessary faulty dimensions in my model and "wrong" snapping nodes that will just make the model messier as the project goes on.

Re: Modeling an overlapping stair. Is it possible?

PVBergkrantz — Tue, 06 Oct 2020 11:33:01 GMT

Yes I agree completely, was just making a bit of fun