Unorthodox stair design: Possible?

[Baphijmm]

Hey there! This might be stupid of me to ask, but I'm gonna ask anyway.

 

I've got this design for a house that was produced for me by an architect; one element of this design is an entry stair which does not conform to what Home Designer seems to consider standard. In particular, the stairway itself is elliptical on the inside, and follow the walls on the outside; the stairs themselves radiate from the center of that ellipse, meaning the rise direction is itself also elliptical.

 

I'm hoping to recreate this design in my Home Designer file, so I can then render it; however, I'm somewhat at a loss for how to do this. Recognizing that the software is based in CAD, I initially attempted to define the space of the stairs as a CAD polyline, only to learn that the CAD ellipse doesn't seem compatible with the CAD lines in the software for the purpose of intersections and re-definition of the polyline space. Further, even with the limited capabilities of what I'd tried, since the conversion from a polyline to another structure is itself limited to only a few possible options, this still wasn't really feasible.

 

Hence, I'm coming here as something of a last resort. I understand that this design is EXTREMELY uncommon as far as Home Designer seems to believe, but I'm absolutely certain that this MUST be possible, given the CAD nature of the software.

 

More specifically, I'm using Home Designer Pro 2023.

[DavidJPotter]

DJP

and here are some additional ones: https://www.youtube.com/results?search_query=winder+stairs+in+Chief+Architect

[solver]

I'd check if that stair will meet code before spending time modeling it.

 

The program will fight your attempts to model it with the stair tool, and the program will win. Too many built in constraints and unwanted automated behaviours.

 

You can do it with landings and it goes fairly quickly.

 

Draw some CAD lines and the ellipse to start. Place a point in the center and draw the first tread (landing).

Use Transform/Replicate to rotate the landing about the Current Point to get you started, then reshape each one as needed.

 

The handrail probably will not work the way you want, but it rarely looks good when using winders.

 

And yes, snaps are a problem

 

[Baphijmm]

Thank you to both of you; the methods presented by each are effectively the same thing, and using that I was able to get the stairs started.

 

My issue at this point is the ellipse itself. While I've defined the ellipse in CAD, it doesn't seem possible to then convert that to anything useful. I tried converting it to a countertop simply to use it as a guide, but that didn't work; understandably, the software converted the ellipse to a large number of lines, which in and of itself isn't a HUGE problem but it's definitely not what I'd intended. Since the curve itself is elliptical, not circular, it seems somewhat challenging, if not impossible, to get the curves to match up if I try simply defining the inner surface of the landing as a curve; additionally, since snapping isn't working basically at all, I can't seem to keep any of my angles consistent.

 

Is there some element I'm missing here? I understand that defining walls from CAD elements isn't supported in Home Designer, but surely the functionality must be there, even if the tool itself is not.

[solver]

20 minutes ago, Baphijmm said:

it doesn't seem possible to then convert that to anything useful

 

Useful how?

 

You are probably not going to get anywhere near perfect.

 

This is trivial in Chief Premier because it has boolean operations -- you simply subtract the ellipse from the landings.

[Baphijmm]

3 minutes ago, solver said:

 

Useful how?

 

You are probably not going to get anywhere near perfect.

 

This is trivial in Chief Premier because it has boolean operations -- you simply subtract the ellipse from the landings.

Haha, see, the boolean tool was something I was kinda hoping I'd find buried somewhere. Alas.

 

As for "Useful how," even being able to define an intersection point between a line and the ellipse would be useful; I could approximate the curves then, which wouldn't be exactly what I'm after but would still be useful. Regarding the previously-mentioned polyline created when I'd attempted to convert the ellipse into something else, naturally none of the lines seemed willing to define an intersect, either.

 

The problem presented is that, this elliptical space between the stairs is then defined by a wall, as below these stairs is another set of similar stairs into a basement; my ultimate goal would be to be able to define this wall.

[y-g-m-n]

Small Question not germane to your drawing issue but I am curious

 

How will this get built?

And is this design comfortable to use and practical for getting to next floor?

 

It is Interesting but as I have found if something is hard to draw it can be even harder to build and impractical.

Also not sure it would be a comfortable climb since it is elliptical.

Each tread depth is different and well if you have ever walked up funky stairs with different tread depth; I find it uncomfortable and I look for handrail to keep from falling.

 

If this was my house I would try to test this out before I committed to this design.

 

I am sure it will be pretty, especially if make from some fine wood but I dunno..

 

Just curious if you have thought this thru.

[Baphijmm]

12 hours ago, y-g-m-n said:

Small Question not germane to your drawing issue but I am curious

 

How will this get built?

And is this design comfortable to use and practical for getting to next floor?

 

It is Interesting but as I have found if something is hard to draw it can be even harder to build and impractical.

Also not sure it would be a comfortable climb since it is elliptical.

Each tread depth is different and well if you have ever walked up funky stairs with different tread depth; I find it uncomfortable and I look for handrail to keep from falling.

 

If this was my house I would try to test this out before I committed to this design.

 

I am sure it will be pretty, especially if make from some fine wood but I dunno..

 

Just curious if you have thought this thru.

The angles are all equivalent, and the stairs are all the same height. While it's true that someone on either side of the stairs would experience them differently, they should still be fairly consistent in any given climb.

 

Fact is, elliptical stairs like these are NOT terribly uncommon; they used to be used quite frequently, and you'll still often see them in government buildings from the 19th century.

 

Additionally, it's EXTREMELY easy to draw; an ellipse is literally just a curve defined by the same total distance from two points. CAD itself has no issue whatsoever drawing these shapes, even segmented into stair treads, and indeed Chief Architect apparently has the necessary tools to draw this up correctly. It's just that Home Designer itself does not have this functionality.

 

In the meantime, I've simply opted to take the "close enough" approach, which is proving somewhat difficult because the software thinks it knows what I want better than I do, but it's getting done.

[y-g-m-n]

Never seen elliptical stairs always squared or just spiral...

I bet they look interesting.

 

good luck with home and plans