Thanks for the help! Added signature, Home Designer Pro 2021 is what I just starting using this past week. I haven't been able to design the platform over the structures as of yet, so you have to imagine that I want a platform over the garage, for example, that would be second floor "base" so as not to confuse terms. I would imagine 2x12' floor joist that would tie into the existing house. On that same level, I would imagine that I would need some type of rubber roofing with a slight pitch to drain water. Within that area, I want and outdoor living area, so decking and railing around the perimeter. I should be able to change the 6" ceiling joist that are there now with a second floor platform. If I could create a second floor over specific areas with railings and no roof, that would go a long way for me. In the original attached image I sent, the "platform" goes over the places where the 6" ceiling joist are.