Challenge: reproduce existing stair as it is

[Anonymous]

Hello guys, I'm trying to reproduce a stair that has been reported during the survey, the main difficulty I have encountered so far are:

• to start the stair with half a winder, so the workaround I found for this is to start from the top of the stair

• and that, on site the end of the stair overlap the start, and archicad don't allow that, the only solution I could figure out would be to draw two separate stairs, but in that case I would have to solve the junction of both of them. If I keep a constant rise/going spacing I have a little empty gap in the structure, and if I join the structure I end up with a shorter riser/going.

I attached a dwg to illustrate more precisely the situation.

[Podolsky]

For Stair like this you don't need to try to reproduce it completely with automatic functions. You need to get same amount of risers, overall shape and after you can adjust each step manually by using edit mode. This is where real power of the new Stair tool, introduced in ArchiCAD 21.

[Anonymous]

Yes I understood this later on while "flexing" the tool, it is ok as far as you have to customize only contour of the whole stair or when you want to reshape the risers and treads finish, but as soon as you need to alter the underneath structure geometry there is no other solution, for my skill level, than either play around with the baseline of the stair or to convert that part to a morph object.
For what I understood till now, I cannot modify one by one the the treads, they are always perpendicular to the baseline of the stair, besides of course for the winders. And in this last case, for example, I cannot "manually" temper with winders to change for example the convergence point of each tread of the winder.
Don't misunderstand me! the stair tool have greatly improved ... may be too much for my skill level 🙂 but in everyday life, I always feel more than often that the reality of built things rarely feet inside our toolbox... and on deadline it is a real PITA, on the other ends it keep things interesting and give a purpose to graphisoft developer :*-)

[Podolsky]

To model existing stair (especially old, built not following any proper standards) always challenge. If manual modification is not giving you what exactly needed, maybe try to split the stair into two? I'm sure it's possible to do it.

[Steve Jepson]

fab wrote:
Hello guys, I'm trying to reproduce a stair that has been reported during the survey, the main difficulty I have encountered so far are:

• to start the stair with half a winder, so the workaround I found for this is to start from the top of the stair

• and that, on site the end of the stair overlap the start, and archicad don't allow that, the only solution I could figure out would be to draw to separate stairs, but in that case I would have to solve the junction of both of them. If I keep a constant rise/going spacing I have a little empty gap in the structure, and if I join the structure I end up with a shorter riser/going.

I attached a dwg to illustrate more precisely the situation.

Quick answer: set slab thickness to 17,7 cm
Use magic wand to create a slab for each tread
View in 3d
Move each thread to the top of the next one.

Now you have an easy and correct model with all the critical nodes you will want to use as you efficiently *model* the stair with easy to adjust parts, profiles.... I have always found it faster and far less frustrating to model what I need to generate for my Interactive Schedules and Shop Drawings - without the Stair Tool.

[Anonymous]

yeah! I am not alone! me too happen to do it that way when I had to draw the stair at a very detailed scale, or when a few time more than a couple of them didn't have the same riser height on the same flight.... a deadly trap for the user, an hell for the draftsman ! they should implement a semi automatic stair tool like this where you can define shape and height independently for each tread step by step so to say! so you don't have to select on all the treads al the bottom corner to get the underneath slab done

[Steve Jepson]

fab wrote:
yeah! I am not alone! me too happen to do it that way when I had to draw the stair at a very detailed scale, or when a few time more than a couple of them didn't have the same riser height on the same flight.... a deadly trap for the user, an hell for the draftsman ! they should implement a semi automatic stair tool like this where you can define shape and height independently for each tread step by step so to say! so you don't have to select on all the treads al the bottom corner to get the underneath slab done

For most of the Stairs I need to model, I usually have one quite similar already. Copy-Paste-Tweak.
The thing is, for the Custom Homes I make Plans for, Stairs are all going to be about the same since studs are usually either 92 5/8" or 104 5/8", and I almost always use (2) 2x6 for the treads = 11".
It's just a matter of how many risers you want. The joists are also usually in a typical range of 2x10's or I-joists. Subfloor is 3/4 or 7/8 most often. With the range/limits for rise and run being pretty much the same for every job it is usually pretty easy to just make some adjustments and be done with it. In a Section view of the stair, you draw a line vertical from subfloor to subfloor and with the Divisions tool you give it the number of risers you want. The nodes on the line will be how you can easily move the adjustable tread-riser objects to the correct elevation. Its a lot easier to do than to describe. And of course, my Interactive Schedules are automatically populated, Shop Drawings are easily generated. I have never spent enough time with the Stair Tool to see what it takes to get out of it what I know I will need. Perhaps there are people who are very good with the stair tool and can genterate the Interactive Schedules and Shop Drawings they need from it - ? I have always been skeptical because I have never actually been able to make it work with out a huge amount t of frustrations and configurations that are never quite right. I just gave up on it.