The floor is not raised it is separated from the walls which pass below the level of the floor the two do not touch. So yes there are 2 heights to the KC 1. From the floor to the ceiling 2. From the base of the walls to the ceiling.
Every major city in the world that has an office dealing in weights and measures has a room such as this.
In Brisbane at Metrology House there is such a room that has a floor seperated from the walls in order to stabilize the floor as much as possible. Anyone can go in a watch measurements being taken.
Next time I get over to Brisbane I will take a pic.
Oh yes for info what is the length of the side of the pyramid measured in metres? In ancient metres 3.3 feet it's 230.4 and this is the socket base.