Tri-level, slab at grade, and foundation

[grateful]

Just getting started with Home Designer Architectural 2021 on Windows 10. 

Designing current layout before implementing remodel changes, and struggling with getting the slab, foundation set up correctly.

 

Details:

1) Main level of house has basement beneath; there is a 2ft cantilever section about 20 ft long on this level also

2) From the main level there are 4 steps down 30" to a family room with slab. The slab then runs down hall/laundry, bath and guest room.

3) End of hall (2 above) has a couple steps up to garage, 15" above slab inside hall, etc.

 

Struggling to get the slabs drawn in. Have tried room type as slab and as garage. The app keeps designing with a floor beneath, but I don't want or have a floor beneath the slabs. When a just change the structure to minimize the height of the forced rooms below it causes all sorts of issues - errors about negative ceilings and problems with 3D views, etc.

 

Appreciate any guidance.

 

Thanks

[solver]

There are various ways of doing, or at least getting close to what you want. 

 

Remember foundations are made up of walls which create rooms just like the structure above. Sometimes the auto foundation builder works, especially for simpler foundations, sometimes you will need to make manual changes.

 

I set a room as Slab and built the foundation in Architectural. Walls on 1st floor set as invisible.

 

Architectural has some limitations too.

 

[Jo_Ann]

If you post the plan file and also a jpeg image of the real house, someone might be better able to help.