Scale Spiral Staircase

I really want to have a spiral staircase somewhere in or around the dollhouse, as I think I've mentioned previously in the album, so I figured that since I'm making the greenhouse two stories anyway, why not put the spiral staircase there? This is the drawing of the to-scale pattern for the spiral staircase which I have been working on. I calculated out how large it would need to be to really work as a scale staircase, as the available spiral staircases to purchase for dollhouses always seem to be not quite the right scale for your average spiral staircase.