I need to build stairs in a very tight space. My only option is winding stairs or a spiral stairs. A spiral staircase is $2000, so I want to build a winding staircase. All the books that I have found explain how to build them come to a point on the inside of the tread. However, code dictates that it can't come to a point, the inside of the tread must be like 4 inches. How to I build a winding staircase that meets building code requirements? If anyone knows of a book or a link that would really help out.

Thanks