Double stairs vs single stairs

[pcas10]

Can someone tell me how to get the double stairs? All I can by are single stairs but when I look at my neighbors stairs it looks like they have a combination. My choice to buy is one set of stairs with a floor at the top.

Thanks for any info on getting double staircase

[DaojinWildfire]

I believe there's only 1 type of stairs at this time. To make your stairs go higher, you can just place another set of stairs on top of what you already have.