Making a floor substrate opaque

[vanderloo5]

I'm illustrating a second level floor plan and lower level roof in the same view. I set the underlay to
Floor 1 so the walls below the roof would show.

I then created a floor substrate above my floor joist with a 3/4" thickness in order to block out the first floor walls below the 2nd floor. I want the substrate to be opaque but I can't get it set that way. I select it, override graphics in view, and set the transparency to 0 but this doesn't work. How can I accomplish this? See attachment. The shaded area is the second floor substrate.
I just want the first floor walls below the upper floor not to show.

Thank You
Attachments:
Attachment Revit_Floor.PNG ‏29 KB

[gustavomello]

I don´t think a overlay can be blocked out by anything, maybe with the exception of a mask, which won´t help you since would mask anything you make on level 2. I would try remove the overlay, make this view´s depth to reach level 1 and set the roofs to transparent for this specific view.

[Dimitri Harvalias]

Similar to your other post, you can do this with plan regions. Set different cut plane and view depth for the 'inside' piece of the roof and the 'outside' piece.