clean room CFD

[Muhamamd]

I have to model clean rooms in the basements of a two story office building. Its like to model a small construction unit inside a big construction unit. IESVE doesn't allow me to do it when I construct something else above the clean room. It gives a message space intersects with an existing space. Should I ignore this and continue or will it effect the results ?

The clean room has its own ceiling and walls and different construction layers. Then there is ceiling of lower ground of office building just 1 meter above clean room ceiling. The office building has its own walls, ceilings and roof. I tried using the connect/merge spaces option without partition but its creates complications in CFD.

Can anyone please guide me how to model this scenario in model IIT.