I encountered concern about unorthodox approaches when building my house: the code says that if you have a central support for the stairs and it is a rectangular pipe of cross section X then it's OK. My staircases floated on a set of plate struts -- basically climbable sculptures designed by the architect. In order to get the permit approved we had to pay someone to write a 15 page book full of differential equations to determine that indeed they wouldn't collapse.

A pain, but worth it.