Hello everyone, I'm currently grappling with the decision between ICF and Precast Insulated Panels for the construction of my new house, particularly for external walls and floors. Although I am leaning towards precast insulated panels, I have some unresolved queries. I intend to build a two-story house with internal dimensions of 8.5m x 8.5m. The attic is envisioned to be 'habitable,' featuring a spare room and a utility room. I am contemplating raising the walls by 0.5m, essentially creating a nearly 2.5-storey structure. Additionally, I am considering a roof pitch of either 8/12 or 7/12. Here are my questions:

1. Does anybody have an idea (with a large approximation) of the potential differences in cost and completion time between ICF and precast insulated walls?
2. For the external rendering of precast insulated walls, is it adequate to paint the concrete, or is another type of rendering (such as stucco) necessary?
3. If rendering is required, what would you pick for optimal durability and maintenance? Should a membrane be installed between the concrete and rendering to prevent trapping humidity/water?
4. Concerning precast insulated walls, is rendering necessary on the interior side, or is it possible to paint the concrete directly?
5. Regarding the floor, if I choose hollow core slabs, are load-bearing walls necessary on the ground floor, considering a span of 8.5m from wall to wall? Additionally, approximately how thick would the floor be?

I appreciate any insights or advice you can offer. Thank you