Narrowing A Spiral Staircase

I’m modelling a lighthouse and I’m trying to narrow this stair case like the lighthouse but I have no idea how to do it, help please? I used this guy’s question for picture.

I would try to deform it with a lattice.

Simple deform (taper in Z axis) works very well here:

You can use a vertex group to control how much the outer radius of the staircase is influenced (above picture: vertex weight 1 on the outer vertices)

Now with vertex weight 0:

I think 0.85 gives a nice trade-off here:

spiral_staircase_taper_1_v01.blend (125.3 KB)


That worked out really well. Thank you!