Build a huge white box house, and take the lawn it displaces and just move it up a level.
Literally “carve out” a piece of the grass-covered site that is used by the building footprint, move it up and treat it as the roofing. Then arrange all the usual required functions 0f the house underneath.
What is most extraordinary about this design, though, is that the huge grass roof is only accessible from inside the house, up these internal grass stairs.
The newly-created roof “deck” space has all the advantages of an outer garden while remaining a safe, internal zone “within” the building.
This structure is not as it first appears; an earthsheltered house tucked into a grassy mound, with a grass stairway entrance down into the house.
It is actually a completely freestanding box shape house. Albeit – with a private grass stairway to a grass roof in the middle of the house! Here you can see the underside of the grass stairway coming down from the roof.
This is a completely original design for a house.
By the Polish architectural firm KWK Promes in Ksiazenice, Poland.