!Restored: Flaw in stair logic

[Anonymous]

The problems with the stair tool stem from a flaw in the logic. The stairs are being defined by where the riser is rather than where the front edge of the stair tread is.

In this post I've attached an image showing a stair that does not have a nosing overhang:
- the 3D matches the 2D; and
- the handrail is the correct height above the nosing of the stair (as stipulated by regulatory requirements).

In the subsequent post I will attach an image of the same stair with a 30 nosing overhang:
- the 3D no longer matches the 2D; and
- the handrail is no longer the correct height above the stair nosing.

These problems occur because the 3D of the stair is being generated by the outside face of the riser rather than the front edge of the tread. The nosing overhang is being added to the front edge of the tread instead of at the back where it should be, with the riser face moving back by the distance of the nosing overhang.

In the real world stairs are set out by their treads, not the risers, and the locations of all of the other elements of the stair is determined relative to where the treads are located.

I'm really surprised that a program as mature as Archicad 11 contains such a fundamental flaw in its logic. It is not reassuring.

[Anonymous]

The lack of a response would seem to indicate that the flaw still exists in Archicad 12.

[Thomas Holm]

mikem wrote:
The lack of a response would seem to indicate that the flaw still exists in Archicad 12.

Mike, I don't have time to test your specific issue. Besides, the final AC12 release might differ from what we testers have today. What I do know is that it's easy to change the railing heights to suit your needs. On the 2D plan display issue, did you try changing the scale as I suggested?

[Laura Yanoviak]

mikem wrote:
The lack of a response would seem to indicate that the flaw still exists in Archicad 12.

Geez -- a little patience -- there is a bit of a time difference don't-you-know.

1) When the nosing dimension changes, the riser moves.
2) The 3D and 2D symbols align.

[Djordje]

Mike,

I am sure that your reseller, that you would be paying the upgrade fee to, would be more than happy to respond immediately.

However, Laura is on the other side of the planet from you, and so is Thomas. So thank them for the effort instead of getting yourself worked up.

Show respect to earn respect.

[Anonymous]

Djorje,

Is Archicad 12 finally (or giving you the option) showing the stairs the way they look in plan from nosing-to-nosing?

Take care,

Wm

[__archiben]

the new, improved 'stairbuilder' for AC12 is probably worth a look too . . .

http://www.cadimagetools.com/news.aspx?id=65

~/archiben

[Anonymous]

Ben, I assume from your post that the cadimagetools stair tool does not contain the logic flaw, and therefore it will model winders correctly.

[Anonymous]

I've received an acknowledgement from Graphisoft Australia that yes there is a problem in the Archicad 11 stair. No comment though on whether the logic flaw still exists in the Archicad 12 stair.

[Steve Jepson]

mikem oz,

The flaw in logic is useing a stair tool, stair maker, stair builder, or any GDL tool for stairs.

Model it!

[Anonymous]

Steve,

I agree with you and I do it all of the time in BOA but Archicad has serious limitations when modeling in its 3-d window. As one of the plug-in writers has pointed out, you cannot easily rotate anything in 3-d. It's too cumbersome and time consuming.

Archicad needs to improve its 3d capabilities or make the plug-in, I forget the name of the product and the company, part of the package.