Re: Glass roof not see-through?

@hannguyen207  Would you like the entire roof to be transparent, or just a section?  If it's the entire roof, or the entire roof above a room, you can simply highlight the room(s) and delete the ceiling.

If you're looking for only a small section of roof to be transparent, first delete the roof you've placed.  Make sure the grid is on (you can toggle it in Build/Buy by hitting the G key), and create a fence around the area you want to be transparent.  This will create a room.  Then you can use the sledgehammer to remove only that section of flooring, place the roof, and remove the fence if you like.