How to create vertical attic stairs?

[PCIconstruction]

Hello everyone,

I want to create something like this. I have shared a link of the stairs I found on the internet. https://euroatticstairs.com/vertical-access-ladder/

Can someone please help me on how to create such a vertical attic hatch and stairs in chief architect x17? 

Thank you in advance. 

[GeneDavis]

Get busy modeling it piece by piece using solids.  Only two or three parts to do, then it's all repeat up a distribution path.  It is an accessory, just like a kitchen cabinet pullout, but I doubt the maker has made a 3D model you can download.